Answer:
Average atomic mass of element X is 56.19 amu
Explanation:
Given:
Four isotopes of X:
5.845% of X has a mass of 53.93961 amu.
91.75% of X has a mass of 55.93494 amu.
2.123% of X has a mass of 56.93539 amu.
0.2820% of X has a mass of 57.93328 amu.
To find: average atomic mass of element X
Solution:
Isotopes are variants of a particular chemical element such that they have the same number of protons but different number of neutrons.
Average atomic mass of element X = [tex]\frac{53.93961+55.93494+56.93539+57.93328}{4}=\frac{224.74322}{4}=56.185805\approx 56.19[/tex]
So, the average atomic mass of element X is 56.19 amu.
PLEASE HELP!!!! How many moles of helium are needed to fill a balloon to a volume of 4.9 at 296°K and 0.78 atm?
Answer:
THE NUMBER OF MOLES OF HELIUM NEEDED TO FILL A BALLOON AT A VOLUME OF 4.9 L AT 296 K AND 0.78 atm IS 0.00338 moles.
Explanation:
The number of moles is calculated using
PV = nRT
P = Pressure = 0.78 atm
V = volume = 4.9 L
R = gas constant = 0.082 Latm/molK
T = temperature = 296 K
n= number of moles
Substituting theses values and sloving for n, we obtain;
n = PV / RT
n = 0.78 * 4.9 / 0.082 * 296
n = 3.822 / 24.272
n = 0.00338 moles.
So therefore, the number of moles is 0.00338 moles.
Answer:
The number of moles of helium needed is 0.157 moles helium
Explanation:
Step 1: Data given
Volume of the balloon = 4.9 L
Temperature= 296 K
Pressure = 0.78 atm
Step 2: Calculate moles of helium gas
p*V = n*R*T
⇒with p = the pressure = 0.78 atm
⇒with V = the volume = 4.9 L
⇒with n = the number of moles of the helium gas = TO BE DETERMINED
⇒with R = the gas constant = 0.08206 L*atm/mol* K
with T = the temperature = 296 K
n = (p*V) / (R*T)
n = (0.78 atm* 4.9 L) / (0.08206 L*atm/mol*K * 296 K)
n = 0.157 moles of helium
The number of moles of helium needed is 0.157 moles helium
Use the nuclear decay reaction in the picture to answer the following question.
i. How does the reaction demonstrate the laws of conservation of charge and conservation of nucleon number?
ii. What is the binding energy of one mole of atomic mass: 234, number of proton: 90, Thorium if the mass defect is 1.908 g/mol?
Answer:
1a. Both sides of the decay reaction have the same charge.
b. The number of nucleons on both sides are the same.
2. The binding energy of one mole of the atom is 17.172 × [tex]10^{16}[/tex] J.
Explanation:
1a. Considering the two sides of the decay reaction and with respect to the law of conservation of charge, it can be observed that both sides have the same charge. Charge can not be created or destroyed in the process.
b. The number of nucleons on both sides are equal. No nucleon is created or destroyed in the process.
2. Binding energy is the minimum energy required to separate an atom into its nucleons. From Einstein's energy equation;
E = Δm[tex]c^{2}[/tex]
Where E is the binding energy of the atom, Δm is the mass defect and c is the speed of light.
Given that: Δm = 1.908 g/mol and c = 3 × [tex]10^{8}[/tex]. So that:
E = 1.908 × [tex](3*10^{8}) ^{2}[/tex]
= 1.908 × 9 × [tex]10^{16}[/tex]
= 17.172 × [tex]10^{16}[/tex] J
The binding energy of one mole of the atom is 17.172 × [tex]10^{16}[/tex] J.
Indicate which molecules demonstrate the correct bonding for carbon atoms. Check all that apply.
CH4
CH3CH4CH2
CH3CH2CH2CH3
CH2CH2CH4
The correct answer is:
CH4
CH3CH2CH2CH3
Answer:
CH4 and CH3 CH2 CH2 CH3
Explanation:
Answer:
CH4 and CH3CH2CH2CH3
Explanation:
its right on edg
Which of the following statements about an S N1 reaction mechanism is true? The reaction involves two steps and occurs fastest with tertiary alkyl halides. The reaction involves one step and occurs fastest with tertiary alkyl halides. The reaction involves one step and occurs fastest with primary alkyl halides. The reaction involves two steps and occurs fastest with primary alkyl halides.
Answer:
The reaction involves two steps and occurs fastest with tertiary alkyl halides
Explanation:
To solve such this we must know the concept of nucleophilic substitution reaction. The reaction involves two steps and occurs fastest with tertiary alkyl halides. Therefore, the correct option is option A.
What is chemical reaction?Chemical reaction is a process in which two or more than two molecules collide in right orientation and energy to form a new chemical compound. The mass of the overall reaction should be conserved. There are so many types of chemical reaction reaction like combination reaction, double displacement reaction.
The characteristics of SN1 mechanism:
SN1 reaction is a nucleophilic substitution reaction.
Leaving group, a nucleophile, electrophile and a solvent are present
Two types of enantiomers can be formed in the reaction depending on the preference of the nucleophile.
The first step is the slowest because a bond is being broken.
SN1 reaction involves two steps and occurs fastest with tertiary alkyl halides
Therefore, the correct option is option A.
Learn more about the chemical reactions, here:
https://brainly.com/question/3461108
#SPJ6
Given the partial equation: MnO4−+ SO32− → Mn2++ SO42−, balance the reaction in acidic solution using the half-reaction method and fill in the coefficients. The missing blanks represent H2O, H+, or OH-, as required to balance the reaction. Enter the coefficients as integers, using the lowest whole numbers. If the coefficient for something is "1", make sure to type that in and not leave it blank. Enter only the coefficients.
Explanation:
MnO4−+ SO32− → Mn2++ SO42−
Splitting into half equations;
MnO4− → Mn2+
SO32− → SO42−
Balancing the electrons;
2 MnO4− + 10 e- → 2Mn2+
5SO32− → 5SO42− + 10 e-
In an acidic medium, it becomes;
2 MnO4− + 8 H+ → 2 Mn2+ + 4 H2O
5 SO32− + H2O → 5 SO42− + 2 H+
Final equation is;
2 MnO4- + 5 SO32- + 6 H+ → 2 (Mn)2+ + 5 SO42- + 3 H2O
Coefficient of H+ = 6
Coefficient of H2O = 3
Coefficient of MnO4- = 2
Coefficient of SO32- = 5
Coefficient of (Mn)2+- = 2
Coefficient of SO42- = 5
Answer:
[tex]5SO_3^{2-}+2MnO_4^{-}+6H^+ \rightarrow 5SO_4^{2-}+ 2Mn^{2+}+3H_2O[/tex]
Explanation:
Hello,
In this case, given the reaction:
[tex]MnO_4^{-}+ SO_3^{2-} \rightarrow Mn^{2+}+ SO_4^{2-}[/tex]
We first identify the oxidation state of both manganese and sulfur at each side:
[tex]Mn^{7+}O_4^{-}+ S^{4+}O_3^{2-} \rightarrow Mn^{2+}+ S^{6+}O_4^{2-}[/tex]
So we have the oxidation and reduction half-reactions below, including the addition of water and hydronium as it is in acidic media:
[tex]S^{4+}O_3^{2-}+H_2O \rightarrow S^{6+}O_4^{2-}+2H^++2e^-[/tex]
[tex]Mn^{7+}O_4^{-}+8H^++5e^- \rightarrow Mn^{2+}+4H_2O[/tex]
Next, we exchange the transferred electrons:
[tex]5*(S^{4+}O_3^{2-}+H_2O \rightarrow S^{6+}O_4^{2-}+2H^++2e^-)\\2*(Mn^{7+}O_4^{-}+8H^++5e^- \rightarrow Mn^{2+}+4H_2O)\\\\5S^{4+}O_3^{2-}+5H_2O \rightarrow 5S^{6+}O_4^{2-}+10H^++10e^-\\2Mn^{7+}O_4^{-}+16H^++10e^- \rightarrow 2Mn^{2+}+8H_2O[/tex]
Then we add the resulting half-reactions and simplify the transferred electrons:
[tex]5S^{4+}O_3^{2-}+5H_2O+2Mn^{7+}O_4^{-}+16H^+ \rightarrow 5S^{6+}O_4^{2-}+10H^++ 2Mn^{2+}+8H_2O[/tex]
We rearrange the terms in order to simplify water and hydronium molecules:
[tex]5S^{4+}O_3^{2-}+2Mn^{7+}O_4^{-}+16H^+-10H^+ \rightarrow 5S^{6+}O_4^{2-}+ 2Mn^{2+}+8H_2O-5H_2O\\\\5S^{4+}O_3^{2-}+2Mn^{7+}O_4^{-}+6H^+ \rightarrow 5S^{6+}O_4^{2-}+ 2Mn^{2+}+3H_2O[/tex]
Finally we write the balanced reaction in acidic media:
[tex]5SO_3^{2-}+2MnO_4^{-}+6H^+ \rightarrow 5SO_4^{2-}+ 2Mn^{2+}+3H_2O[/tex]
Best regards.
How is a niche different than a habitat?
A habitat is more than a physical place; it's a species' role in a specific place and it can change from niche to niche.
A niche is more than a physical place; it's a species' role in a specific place and it can change from habitat to habitat.
A niche and a habitat are the same.
A niche is just a physical place; a habitat is a species' role in a specific place.
Answer:
A niche is more than a physical place; it's a species' role in a specific place and it can change from habitat to habitat.
Explanation:
Niche: In biology, the term "niche" is described as a process through which different organisms tends to fit-in into a specific ecosystem or an ecological community. However, a niche is considered as the "evolutionary result" of a specific species behavioral, morphological, and physiological adaptations associated with its surroundings.
Habitat: In biology, the term "habitat" is described as an environmental or ecological area that is being inhabited by a specific species of plants, animals, or other organisms.
Therefore, a niche is entirely different from a habitat because an organism's niche tends to explain every different aspect of its life whereas its habitat explains the place it lives.
the rule of eight chemistry
Answer:
octet rule
Explanation:
It refers to the tendency of atoms to prefer to have eight electrons in the valence shell.
Two identical light bulbs are connected to a battery in a series circuit.
An ammeter is wired into the circuit at measures a current of the
battery to be 0.5 Amps. The two light bulbs are then wired in parallel.
The ammeter shows that the current:
Answer:
0.10 amps
Explanation:
Pure water at 25°C ionizes as what?
Answer:
see explanation
Explanation:
Pure water (H₂O) at 25°C follows an autoionization mechanism. That is, water reacts with itself to yield Hydronium Ions (H₃O⁺) and Hydroxide Ions (OH⁻) according to the following proton transfer mechanism.
2H₂O(l) ⇄ H₃O⁺(aq) + OH⁻(aq) => H₂O(I) ⇄ H⁺(aq) + OH⁻(aq) as a shorthand form of the process primarily for convenience. The H⁺ ion is a proton and would not be found in solution as an independent free form particle, but the shorthand format is generally accepted in the chemical community because of it's ease of application.
Other related facts of water ionization include...
At 25°C/1atm => the molar concentrations of [H⁺(aq)] = 1 x 10⁻⁷M and [OH⁻(aq)] = 1 x 10⁻⁷M
Applying to the equilibrium ionization expression for water ...
H₂O(I) ⇄ H⁺(aq) + OH⁻(aq)
C(eq): ∞* 1 x 10⁻⁷M 1 x 10⁻⁷M
*The molar concentration of water is considered to be infinite [∞] as compared to concentration values of H⁺(aq) and OH⁻(aq) and is for practical purposes assumed to be constant. This leads to the classic Ionization Product constant expression for water (Kw = [H⁺(aq)][OH⁻(aq)].
The value for Kw at 25°C/1atm is then ...
Kw = [H⁺(aq)][OH⁻(aq)] = (1 x 10⁻⁷M)(1 x 10⁻⁷M) = 1 x 10⁻¹⁴M² (units are typically dropped and Kw listed simply as 1 x 10⁻¹⁴.
With this, the terms acidity, neutral and alkaline acid base systems are defined and related to pH. That is, if ...
[H⁺(aq)] > [OH⁻(aq)] => Acidic System => pH < 7
[H⁺(aq)] = [OH⁻(aq)] => Neutral System => pH = 7
[H⁺(aq)] < [OH⁻(aq)] => Alkaline System => pH < 7
pH = -log[H⁺] and pOH = -log[OH⁻] and pH + pOH = 14.
A container is filled with 10 mol of gas and the pressure (Pi) is measured. If 5 mol are removed, what is the new pressure (Pf)?
Answer:
1/2 of the Pi
Explanation:
PV = nRT
we are going to assume the only things changing are pressure and number of mols, so we change the formula and substitute the variables to make it what we are looking for
[tex]\frac{Pi}{ni} = \frac{Pf}{nf}[/tex]
then we will assume Pi as 1 as it is not given, so we can state it easier
[tex]\frac{1atm}{10mol} = \frac{xatm}{5mol}[/tex]
then either cross multiply or just work it out to be
[tex]\frac{1}{2}[/tex] which we can say as "half of the initial pressure" as no number is given for initial pressure
3. Infer A forgotten ice pop lies melting on a deck on a hot summer day. What is the direction of heat flow as the ice pop melts?
Is the process endothermic or exothermic? Explain.
Answer:
Endothermic. The energy is flowing into the molecules causing them to break apart and the ice pop change state.
Answer:
Yes, an autumn day isn’t cold enough to keep an ice pop at freezing temperatures.
Rate Law & Reaction Kinetics Chemistry 11 Chapter 17 1. For the reaction 3 ClO - (aq) → ClO - 3(aq) + 2 Cl - (aq) doubling the concentration of ClO - quadruples the initial rate of formation of ClO - 3 . What is the rate expression for the reaction? 2. The reaction C 6 H 5 N 2 Cl (aq) + H 2 O (l) → C 6 H 5 OH (aq) + N 2(g) + HCl (aq) is first order in C 6 H 5 N 2 Cl and zero order in H 2 O. What is the rate expression? 3. For the reaction H 3 PO 4(aq) + 3I - (aq) + 2H + (aq) → H 3 PO 3(aq) + I - 3(aq) + H 2 O (l) the rate expression under certain conditions is R = k[H 3 PO 4 ][I - ][H + ] 2 . What method(s) could be used if you want to double the reaction rate? 4. What is the overall order of reaction for each of the following: a) R = k[NO 2 ] 2 b) R = k c) R = k[H 2 ][Br 2 ] ½ d) Rate = k[NO] 2 [O2]
Answer:
1) Rate = K [ClO⁻]²
2) Rate = K [C6H5N2Cl]
3) - Double the concentration of H3PO4.
- Double the concentration of I⁻
4) Check Explanation
Explanation:
A reaction's rate law is written as a product of the reaction's rate constant, k, and the concentration of the respective reactant(s) raised to the power of the order of reaction.
The order of a reaction with respect to a reactant is the power that the concentration of that specific reactant has in the rate law. It shows how dependent on each reactant , the rate of the reaction.
1) 3ClO⁻ (aq) → ClO³⁻ (aq) + 2 Cl⁻ (aq)
Doubling the concentration of ClO⁻ quadruples the initial rate of formation of ClO³⁻. What is the rate expression for the reaction?
Rate = k [ClO⁻]ⁿ
When [ClO⁻] is doubled, Rate is quadrupled, this shows that the reaction is second order with respect to the only reactant.
Rate = K [ClO⁻]²
2. The reaction
C6H5N2Cl (aq) + H2O (l) → C6H5OH (aq) + N2 (g) + HCl (aq) is first order in C6H5N2Cl and zero order in H2O. What is the rate expression?
Normally, the rate of reaction is equal to the rate constant multiplied by the each reactant's concentration raised ti the power of the order, so,
Rate = K [C6H5N2Cl]¹ [H2O]
Rate = K [C6H5N2Cl]
3. For the reaction
H3PO4 (aq) + 3I⁻ (aq) + 2H + (aq) → H3PO3(aq) + I³⁻(aq) + H2O
(l) the rate expression under certain conditions is R = k[H3PO4][I⁻][H⁺]² . What method(s) could be used if you want to double the reaction rate?
Rate = k[H3PO4][I⁻][H⁺]²
Indicating a first order relationship between the rate and the concentration of H3PO4 & I⁻ and second order with respect to H⁺.
So, any attempt to double the rate of reaction will entail a direct doubling of the one of the reactants with a first order relationship with the rate of reaction.
4. What is the overall order of reaction for each of the following.
a) R = k[NO2]² b) R = k c) R = k[H2][Br2] ½ d) Rate = k[NO]² [O2]
Note that overall order of a reaction is the sum of all the orders of the reactants that appear in the rate law.
a) R = k[NO2]²
Overall order is obviously 2.
b) R = k
Overall order is evidently 0.
c) R = k [H2] [Br2]^ ½
Overall order = 1 + ½ = (3/2)
d) Rate = k[NO]2 [O2]
Overall order = 2 + 1 = 3
Hope this Helps!!!
which sublevels contain valence electrons in an atom of nitrogen
Sublevel 2s and 2p contains the valence electrons for nitrogen.
which of the following is associated with the use of genetic engineering to clone farm
animals?
A.
Cloning could improve the availability of food in some areas
B.
The success rate for animal cloning is currently low.
C.
There is controversy associated with cloning farm animals
D.
all of these
Answer:D all of these
Explanation:
I just did it and that’s the correct answer
which statement best describes the formation of h20(g)?
Answer:
wHeRe ArE tHe StAtEmEnTs mAn
When you add a controlled amount of substance known as an impurity to a pure semiconductor, its conductivity increases. This process is known as doping. The addition of an impurity can increase or decrease the number of available electrons. If the number of electrons is increased, the extra electrons conduct electricity. If the number of electrons is decreased, a vacant hole is created. The adjacent electron enters the vacant hole and conducts electricity. Thus, it seems like the holes act as charge carriers. They are considered to be positive charge carriers. Depending upon the charge carriers that conduct electricity, there are two types of semiconductors: p-type semiconductors and n-type semiconductors.Which of the following statements are correct with respect to semiconductors?
a) The addition of group 3A elements to group 4A semiconductors decreases the conductivity of the group 4A semiconductors.
b) The conductivity of semiconductors can be increased by the doping process.
c) As the temperature increases, the conductivity of semiconductors decreases.
d) The addition of group 5A elements to group 4A semiconductors increases the conductivity of the group 4A semiconductors.
e) Holes are charge carriers in p-type semiconductors.
f) Electrons are charge carriers in n-type semiconductors.
Answer:
See explaination
Explanation:
1. The addition of group 3A elements to group 4A semiconductors decreases the conductivity of the group 4A semiconductors: Wrong
The addition of 3A group elements inreases the conductivity and make them extrinsic semiconductors( p-type)
2. The conductivity of semiconductors can be increased by the doping process.: Correct
3.As the temperature increases, the conductivity of semiconductors decreases.. wrong
As the temperature increases, the conductivity of semiconductors increases.
4. The addition of group 5A elements to group 4A semiconductors increases the conductivity of the group 4A semiconductors: Correct : They will create n-type semicoductor.
5.Holes are charge carriers in p-type semiconductors: Correct
6. Electrons are charge carriers in n-type semiconductors: Correct
The first step that you will do in lab is to prepare approximately 20.0 mL each of the following solutions of NaOH, using the NaCl solution to dilute the concentrated (0.300 M) solution of NaOH. After you prepare each solution, transfer it to a clean 50 mL beaker on top of a labeled piece of paper. 0.200 M NaOH 0.150 M NaOH 0.100 M NaOH 0.050 M NaOH 0.025 M NaOH
Answer:
0.200 M NaOH: 13.3 mL of the concentrated solution and complete to 20.0mL
0.150 M NaOH: 10.0 mL of the concentrated solution and complete to 20.0mL
0.100 M NaOH: 6.67 mL of the concentrated solution and complete to 20.0mL
0.050 M NaOH: 3.33 mL of the concentrated solution and complete to 20.0mL
0.025 M NaOH: 1.67 mL of the concentrated solution and complete to 20.0mL
Explanation:
It is possible to prepare a solution from a more concentrated one. In the problem, the concentrated solution is 0.300M NaOH. Thus, to prepare 20.0mL of each of the solutions you will need:
0.200 M NaOH: 20.0mL × (0.200M / 0.300M) = 13.3 mL of the concentrated solution and complete to 20.0mL
The ratio between the concentrated solution and the solution you want to prepare is called "dilution factor"
0.150 M NaOH: 20.0mL × (0.150M / 0.300M) = 10.0 mL of the concentrated solution and complete to 20.0mL
0.100 M NaOH: 20.0mL × (0.100M / 0.300M) = 6.67 mL of the concentrated solution and complete to 20.0mL
0.050 M NaOH: 20.0mL × (0.050M / 0.300M) = 3.33 mL of the concentrated solution and complete to 20.0mL
0.025 M NaOH: 20.0mL × (0.025M / 0.300M) = 1.67 mL of the concentrated solution and complete to 20.0mL
Consider mixing a liquid with a vapor pressure of 100 torr with an equimolar amount of a liquid with a vapor pressure of 200 torr. The resulting solution would be predicted to have a vapor pressure of 150 torr if it behaved ideally. If, however, the interactions between the different components are not similar we can see positive or negative deviations from the calculated vapor pressure. An actual vapor pressure greater than that predicted by Raoult's law is said to be a positive deviation and an actual vapor pressure lower than that predicted by Raoult's law is a negative deviation.
Part A
Imagine a solution of ftwo liquids in which the molecules interact less favorably than they do in the individual liquids Will this solution deviate posltively from, deviate negatively from, or idealy follow Raouit's law?
a. It will deviate positively.
b. It will deviate negatively.
c. It will be an ideal solution
Part B
Imagine a solution of two iquids in which the molecules interact more favorably than they do in the individual liquids Will this solution deviate positively from, deviate negatively from, or ideally follow Raoult's law?
a. It will deviate positively. b. It will deviate negatively. c. It will be an ideal solution
Answer:
b. a.
Explanation:
0
Why does a hot water bottle feel warm?
Molecules in the hot water bottle are
moving faster than molecules in the skin.
Molecules in the skin are moving faster
than molecules in the hot water bottle.
DONE
Answer:
Molecules in the hot water bottle are
moving faster than molecules in the skin.
Explanation:
Answer:
The first one "Molecules in the hot water bottle are
moving faster than molecules in the skin.''
Explanation:
How to make isopropyl alcohol
Answer:
.It is easily synthesized from the reaction of propylene with sulfuric acid, followed by hydrolysis. Isopropyl alcohol (2-propanol) is made by indirect hydration of propylene (CH2CHCH3).… In some cases the hydration of propylene is carried out in one step, using water and a catalyst at high pressure.
Hope it'll help!
stay safe:)
A sample of gas at occupies 10m3 at a pressure of 120 kPa. If the volume of the sample is changed to 3m3, what is the new pressure of the gas?
Answer:
400 kPa
Explanation:
Please see the step-by-step solution in the picture attached below.
Hope this answer can help you. Have a nice day!
Answer:
400 kPa
The answer is right since its from ck12
is silver malleable because the valence electrons are strongly attracted to the nucleus
I'll give you 100 points
Which are evidence of seafloor spreading? Select three options. A.molten material B.magnetic stripes C.continent material D.drilled core samples E.ocean water samples
Salt in crude oil must be removed before the oil undergoes processing in a refinery. The
crude oil is fed to a washing unit where freshwater fed to the unit mixes with the oil and
dissolves a portion of the salt contained in the oil. The oil (containing some salt but no
water), being less dense than the water, can be removed at the top of the washer. If the
“spent” wash water contains 15% salt and the crude oil contains 5% salt, determine the
concentration of salt in the “washed” oil product if the ratio of crud oil (with salt) to
water used is 4:1.
Answer:
[tex]\large \boxed{0.64 \, \%}[/tex]
Explanation:
Assume you are using 1 L of water.
Then you are washing 4 L of salty oil.
1. Calculate the mass of the salty oil
Assume the oil has a density of 0.86 g/mL.
[tex]\text{Mass of oil} = \text{4000 mL} \times \dfrac{\text{0.86 g}}{\text{1 mL}} = \text{3440 g}[/tex]
2. Calculate the mass of salt in the salty oil
[tex]\text{Mass of salt} = \text{3440 g} \times \dfrac{\text{5 g salt}}{\text{100 g oil}} = \text{172 g salt}[/tex]
3. Calculate the mass of salt in the spent water
[tex]\text{Mass of salt} = \text{1000 g water} \times \dfrac{\text{15 g salt}}{\text{100 g water}} = \text{150 g salt}[/tex]
4. Mass of salt remaining in washed oil
Mass = 172 g - 150 g = 22 g
5. Concentration of salt in washed oil
[tex]\text{Concentration} = \dfrac{\text{22 g}}{\text{3440 g}} \times 100 \, \% = \mathbf{0.64 \, \%}\\\\\text{The concentration of salt in the washed oil is $\large \boxed{\mathbf{0.64 \, \%}}$}[/tex]
In a different experiment, the student uses a calorimeter which is perfectly insulated. She fills the calorimeter with 100.0 g of 25.00°C dilute HCl solution and adds 0.594 g Mg metal (24.3 g/mol). The final temperature of the apparatus comes to 41.83°C. Remember, the solution is made-up of the solute and the solvent. The specific heat for magnesium is negligible compared to the aqueous solution. What is the Molar Heat of Enthalpy for this reaction?
Answer:
Explanation:
Mg + 2HCl = Mg Cl₂ + H₂
.594 g = .594 / 24.3
= .02444 mole
Heat evolved = msΔ T , m is mass of water ( solvant ) , s is specific heat of water , Δ T is rise in temperature
= 100 x 4.2 x ( 41.83 - 25 )
= 7068.6 J
.02444 mole of Mg evolves 7068.6 J of heat
1 mole of Mg evolves 7068.6 /.02444 J
= 289222.6 J
= 289 kJ .
Molar heat enthalpy = 289 kJ .
18.35 mL of an HCN solution were titrated with 35.4mL of a 0.268M NaOH solution to reach the equivalence point. What is the molarity of the HCN solution
Answer:
0.517
Explanation:
HCN + NaOH → NaCN + H2O [balanced as written]
(35.4 mL) x (0.268 M NaOH) x (1 mol HCN / 1 mol NaOH) / (18.35 mL HCN) = 0.517 M HCN
Answer: 0.517
Explanation:
What is the symbol for the entity that has 17 protons, 20 neutrons, and 18 electrons?
hEy!!!
Chlorine(CL) is the symbol for the entity that has 17 protons,20 neutrons and 18 electrons.
Hope it will be helpful to you...
Answer:chlorine
Explanation:
what is the percent composition of muscovite mica. Its chemical formula is
(KF)2(Al2O3)3(SiO2)6(H2O)
Answer:
[tex]\boxed{\text{0.25 \% H, 43.96 \% O, 4.75 \% F, 20.22 \% Al, 21.05 \% Si, 9.77 \% K}}[/tex]
Explanation:
The oxide formula is (KF)₂(Al₂O₃)₂(SiO₂)(H₂O).
Rewrite it as a molecular formula — H₂O₂₂F₂Al₆Si₆K₂
The formula for the mass percent of an element is
[tex]\text{Mass \%} = \dfrac{\text{mass of element}}{\text{mass of compound}} \times 100 \, \%[/tex]
We can set up a table to calculate the percent of each element.
[tex]\begin{array}{rrrrr}\textbf{Atom} & \textbf{No.} &\textbf{MM/u} & \textbf{Mass/u} & \mathbf{\%} \\\text{H} & 2& 1.01 & 2.02& 0.25 \\\text{O} &22 & 16.00 & 351.98 & 43.96 \\\text{F} & 2 & 19.00 & 38.00 & 4.75 \\\text{Al} & 6 & 26.98 & 161.89 & 20.22 \\\text{Si} & 6 & 28.08 & 168.51 & 21.05 \\\text{K} & 2 & 39.10 & 78.20 & 9.77 \\& & \text{TOTAL =} & \mathbf{800.60} & \mathbf{100.00} \\\end{array}\\[/tex]
[tex]\text{The percent composition of muscovite mica is}\\ \boxed{\textbf{0.25 \% H, 43.96 \% O, 4.75 \% F, 20.22 \% Al, 21.05 \% Si, 9.77 \% K}}[/tex]
5 Which state of matter takes both the shape and volume of its container?
liquid
solid
gas
Answer:
gas
Explanation:
If you put gas in anything, it will occupy shape and volume.
Liquid only occupies shape of the container, whereas, solid doesn't occupy shape or volume because it maintains a fixed volume and shape.
Using Boyle's Law solve the following: An unknown gas has a volume of 200.0 mL and a pressure of 350.0 torr, pressure were increased to 700.0 torr, what is the resulting volume?
Answer:
400 mL
Explanation:
Boyle's Law: [tex]P_1*V_1 = P_2*V_2[/tex]
Let x = the resulting volume
350 (200) = 700 (x)
x = 400 mL
