PLEASE HELP
Answer the following about this chemical equation: Na + MgF2 ---> NaF + Mg
What are the reactants?
What are the products?
Is the equation balanced?
Answer:
The reactants are the first two before the arrow and the products are the last two after the arrow, it is not balanced it would look like this if it was balanced:
2Na+MgF2–>2NaF+2Mg
A sample initially contains 8.0 moles of a radioactive isotope. How much of the sample remains after four half-lives? Express your answer using two significant figures.
Answer:
0.50 mol
Explanation:
The half-life is the time required for the amount of a radioactive isotope to decay to half that amount.
Initially, there are 8.0 moles.
After 1 half-life, there remain 1/2 × 8.0 mol = 4.0 mol.After 2 half-lives, there remain 1/2 × 4.0 mol = 2.0 mol.After 3 half-lives, there remain 1/2 × 2.0 mol = 1.0 mol.After 4 half-lives, there remain 1/2 × 1.0 mol = 0.50 mol.What occurs in electroplating?
Deposition of a metal layer on a material
Deposition of a salt layer on a metal
Decomposition of a salt layer
Decomposition of a metal layer
Answer the question pls answer this and it’s due in 4 minutes!!. Help
Answer:
the first one is gas and the second one is liquid
Isabel and Ruth scored a total of twenty-two points in their last basketball game scored two more points than Isabelle.How many points did Isabel score?
A:2x-2=22; x=12
B:x+2=22; x=20
C:2x+2=22; x=10
D:2x+2=22; x=12
isabel is represented as x
ruth is represented as x+2
so the equation would be
x+(x+2)=22
the (x+2) is ruth. so to check if its right solve it. 2x+2=22
-2 -2
2x+20
__ ___
2 2
x=10
so now you know that isabel scored 10 goals since she was x. to figure out ruth just add 2.
What is the maximum amount of ammonia that can be produced when 0.35 mol Nz reacts with 0.90 mol Hz?
Answer:
0.6 moles NH₃
Explanation:
The reaction that takes place is:
N₂ + 3H₂ → 2NH₃First we determine the limiting reactant:
0.35 mol N₂ would react completely with (3*0.35) 1.05 moles of H₂. There are not as many H₂ moles, so H₂ is the limiting reactant.Then we convert H₂ moles (the limiting reactant) to NH₃ moles, keeping in mind the stoichiometry of the reaction:
0.90 mol H₂ * [tex]\frac{2molNH_3}{3molH_2}[/tex]= 0.6 moles NH₃Describe how you could feel weightless on Earth.
Select the correct answer.
In this course, you will be learning about which of the following topics:
A. Advantages and challenges of Childcare
B. Organizational Skills
C. Home Safety
D. All of the above
D?
Explanation:
considering they're all similar options I'd assume D, but there isn't any context
what are some characteristics of the structure of DNA
Answer:
Explanation:
DNA is composed of two side-by-side chains (“strands”) of nucleotides twisted into the shape of a double helix. ...
The bases are attached to the 1′ carbon of each deoxyribose sugar in the backbone of each strand. ...
The association of A with T and G with C is through hydrogen bonds
Question 54
Which one of the following substances is classified as a molecular element?
a.KCI
b.12
c. NO
d.CO
e. C6H12O6
I2 is classified as a molecular element.
A molecular element is a molecule that is composed of two or more atoms of the same type that are chemically joined together.
The substance that fits this description is I2. It consists of two iodine atoms joined together.
Hence, I2 is classified as a molecular element.
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g Predict the hybridization about the central atom in the given structure. A molecule with atom Y single bonded with 3 X substituents. The Y atom has two lone pairs.
Answer:
sp3d
Explanation:
The Central atom Y is singly bonded to 3 X substituents and it has two lone pairs.
An example of compound that fits this description is BrF3.
The central atom used d orbitals for hybridization.
The 2 lone pair plus three single bond equals 5.
As the hybridization value is equal to 5 it gives rise to sp3d hybrid orbitals.
How many grams of H2O are needed to produce 150. g of Mg(OH)2?
Mg3N2(s) + 6H2O(l) → 3Mg(OH)2(aq) + 2NH3(g)
Answer:
About 92.67 grams of H2O are required
Explanation:
The easier way for some people is to work backwards.
Since we already have the amount of grams produced (for Mg(OH)2), we can just start from there.
In order to find the amount of grams of H2O needed we need to know the amount of moles actually used in the chemical reaction.
We can find this using the balanced chemical equation to convert from grams of Magnesium Hydroxide to moles of Magnesium Hydroxide to moles of Water and finally to grams of Water.
**58.319 g is the amu (molar mass) of Mg(OH)2
Step 1 -> 150 g Mg(OH)2 * [tex]\frac{1 mol Mg(OH)_{2} }{58.319 g Mg(OH)_{2} }[/tex] = 2.572060563 moles
We can round that to 2.572 moles of Mg(OH)2 produced.
Step 2 -> Now we can convert from moles of Mg(OH)2 to moles of H2O
We will do this using the balanced chemical equation
2.572 moles Mg(OH)2 *[tex]\frac{ 6 moles H2O}{3 moles Mg(OH)2}[/tex] = 5.144 moles of H2O required
Step 3 -> Now we will convert from moles of H2O (water) to grams
**Using the amu (molecular mass)
The molecular mass of water is about 18.015 grams
5.144 moles * [tex]\frac{18.015 grams H_{2}O }{1 mol H_{2}O}[/tex] = 92.66916 grams of H2O
So, about 92.67 grams of H2O are required
what is photosynthesis
Answer:
the process by which green plants and some other organisms use sunlight to synthesize foods from carbon dioxide and water. Photosynthesis in plants generally involves the green pigment chlorophyll and generates oxygen as a byproduct.
Explanation: You can put this in your own words. How? Well, try to find the most important stuff in your own words and write it down.
HELP PLS THIS IS DUE IN 5 MINUTES!!
Answer:
it is a soft and very cold molocules but at the touch of a hand it will melt because of how compact the molocules are
Explanation:
gallium can only stay a solid under 85.59°F so is someone had is in there had is would end up like ice cream
How was the periodic law rearranged to become the periodic table, and what is its purpose?
Answer:
At earlier times elements were arrangrd on the basis of their atomic masses to study their properties easily but there were various problems like isotopes needs different position in perodic table.
After discovery of atomic number modern periodic table was created on the basis of atomic number (number of proton) that is unique for each element and varies regularly. So study of a group of elements is much easier than each element seperately that is why modern periodic table was formed.
Explanation:
Which factor affects a solute's solubility rather than its rate of solution?
OA. Nature of the solvent
O B. Size of solute particles
OC. Amount of solute particles
O D. Shaking of the solvent
Answer: A
Explanation:
I took the test it was A
which statement best describes an example of selective breeding?
Answer:
B people control how plants or animals reproduce to get desired traits
Explanation:
if you get it correct mark meh brainliest or however you say it so ppl know its correct
every spring has an equilibrium position. which statement describe a spring at its equilibrium postion? Check all that apply.
Answer:
The elastic potential energy is zero.
The net force acting on the spring is zero.
have a great day <333
A chemist measures the mass of an unknown substance. The mass is 2.53 g. Which statement best describes the chemist measurement
a : it’s is a qualitative inference
b : it is a quantitative inference
c : it is a qualitative observation
d : it is quantitative observation
Answer:
D) it is quantitative observation
The chemist measurement is a quantitative inference and the correct option is option B.
What is the difference between quantitative and qualitative measurement?Quantitative means measuring a quantity - putting a value to something.
For example, The rate of a reaction can be measured by measuring the time it takes for a change to happen, such as the time taken for a piece of magnesium ribbon to dissolve in acids of different concentrations.
Qualitative means without determining a value.
This is usually done by making a comparison, e.g. the magnesium dissolves more quickly in this acid than in that one, or making observations like lithium compounds produce a red flame colour while sodium compounds produce a yellow one.
Therefore, the chemist measurement is a quantitative inference and the correct option is option B.
Learn more about Quantitative and Qualitative measurement, here:
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19. H2O, CO2, CaCl2, and Na2CO3 (the numbers are subscripts) are all examples of that tell which atoms and how much of each atom is needed to make a molecule of a substance.
A.chemical formulas
B.types of atoms
C.elements
Answer:
A. Chemical formulas
Explanation:
Hello!
In this case, since chemical formulas are written or drawn representations of what atoms and how much of them are present in a molecule, which is composed by two or more different atoms, we can infer that molecules such as H2O (water), CO2 (carbon dioxide), CaCl2 (calcium chloride) and Na2CO3 (sodium carbonate) are given as a. Chemical formulas, because we can see there are two hydrogens and one oxygen in water, one carbon and two oxygens in carbon dioxide, one calcium and two chlorines in calcium chloride and two sodiums, one carbon and three oxygens in sodium carbonate.
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What is the mass percentage of JUST water in the hydrate CuSO4 ∙5H2O? The molar mass for the whole compound is 249.71 g/mol.
answer: 29x90=103
Kjjjj
PLSSSSSSSSS HELP!!!!!!!! FIRST TO AWNSER GETS BRAINLIEST!!!!!!!!
Research four illnesses that afflict humans. Each illness should be caused by a pathogenic organism of a different type:
an illness caused by a bacterium
an illness caused by a virus
an illness caused by a fungus
an illness caused by a protist
Answer:
measles are caused by virus
strep throat is caused by bacterium
aspergillosis caused by fungus
malaria caused by protist
hope this helps!
Explanation:
How is a warm front formation diffrent from occlued front formation
Answer: Two cold air masses surround a warm air mass during a warm front, but a cold air mass moves against a warm air mass during an occluded front.
You are given 4.92 grams of H2O. How many moles is that?
Answer:
0.273 mol H₂O
General Formulas and Concepts:
Chemistry - Atomic Structure
Reading a Periodic TableUsing Dimensional AnalysisExplanation:
Step 1: Define
4.92 g H₂O
Step 2: Identify Conversions
Molar Mass of H - 1.01 g/mol
Molar Mass of O - 16.00 g/mol
Molar Mass of H₂O - 2(1.01) + 16.00 = 18.02 g/mol
Step 3: Convert
[tex]4.92 \ g \ H_2O(\frac{1 \ mol \ H_2O}{18.02 \ g \ H_2O} )[/tex] = 0.27303 mol H₂O
Step 4: Check
We are given 3 sig figs. Follow sig fig rules and round.
0.27303 mol H₂O ≈ 0.273 mol H₂O
please help me I will give a brainleist to anyone who answers
Answer:
4
Explanation:
Which element has 6 valence electrons? The Periodic Table O A. Carbon (C) O B. Barium (Ba) O C. Selenium (Se) O D. Lithium (Li)
Answer:
c) selenium
Explanation:
Selenium is present in group sixteen.
It has six valance electrons.
Its atomic number is 34.
Atomic mass of selenium is 78.96 amu.
Electronic configuration pf selenium:
Se₃₄ = 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁴
we can see there are six valance electrons are present in selenium (4s² 4p⁴).
Valance electrons are those electrons which are present in outer most electronic shell.
Other options are incorrect because,
There are 4 valance electrons in carbon.
2 valance electrons of barium.
one valance electron of lithium.
7,5,3,6,9
what three numbers add up to 12
Explanation:
3+3+6=12 is the three numbers adding up to 12
Calculate the number of gold atom
present in 0.6g of 18 carat gold (24 carat
gold is taken as 100%
where and amu of
gold in 197
Teacher's Signature.
The number of gold atom : 1.204 x 10²¹
Further explanationGiven
0.6 g of 18 carat gold
mass number of gold = 197
24 carat as 100% gold
Required
The number of gold atom
Solution
Percentage of gold in 18 carat :
[tex]\tt \dfrac{18}{24}\times 100\%=75\%[/tex]
Mass of gold in 0.6 g of 18 carat :
[tex]\tt 75\%\times 0.6~g=0.45~g[/tex]
mol :
[tex]\tt mol=\dfrac{mass}{MW}=\dfrac{0.45}{197}=0.0023[/tex]
A mole is a number of particles(atoms, molecules, ions) in a substance
1 mole = 6.02.10²³ particles
So the number of gold atom :
[tex]\tt 0.0023\times 6.02\times 10^{23}=1.204\times 10^{21}[/tex]
The air in a 4.50 L tank has a pressure of 1.40 atm . What is the final pressure, in atmospheres, when the air is placed in tanks that have the following volumes, if there is no change in temperature and amount of gas?
a. 1.00 L
b. 2500. mL
c. 750. mL
d. 8.00 L
Answer:
a. 6.30 atm.
b. 2.52 atm.
c. 8.40 atm
d. 0.788 atm
Explanation:
Hello!
In this case, since the Boyle's law was proposed in order to understand how the volume and pressure are related via an inversely proportional relationship:
[tex]P_2V_2=P_1V_1[/tex]
In order to compute the final pressure we use:
[tex]P_2=\frac{P_1V_1}{V_2}[/tex]
Therefore we proceed by using same volume units as follows:
a.
[tex]P_2=\frac{4.50L*1.40atm}{1.00L}=6.3atm[/tex]
b.
[tex]P_2=\frac{4.50L*1.40atm}{2.5L}=2.52atm[/tex]
c.
[tex]P_2=\frac{4.50L*1.40atm}{0.750L}=8.4atm[/tex]
d.
[tex]P_2=\frac{4.50L*1.40atm}{8.00L}=0.788atm[/tex]
Best regards!
what's the importance of anatomy for pharmacy students
All health professionals, including pharmacists, must be able to relate form to function..a grounding in anatmony is an essential foundation on which to underpin other knowledge relevant to clinical practice.
