Answer:
b calcium
Explanation:
CHEM HELP PLS 30 POINTS!!
1. what volume of 0.20 M HCl (aq) is needed to titrate 50 mL of 0.10 M NaOH to the endpoint?
A) 10.0 mL HCl
B) 40.0 mL HCl
C) 25.0 mL HCl
D) 20.0 mL HCl
2. what is the molarity of a NaOH solution if 40 mL of the solution is titrated to the endpoint with 15 mL of 1.50 M H2SO4?
A) 1.13 M
B) 1.47 M
C) 0.56 M
D) 0.75 M
3. suppose that 10.0 mL of HNO3 is neutralized by 71.4 mL of a 4.2 x 10 ^ -3 M solution of KOH in a titration. Calculate the concentration of the HNO3 solution.
A) 1.0 x 10 ^ -2 M
B) 3.0 x 10 ^ -2 M
C) 5.5 x 10 ^ -2 M
D) 1.0 x 10 ^ -14 M
Balanced equation
HCl + NaOH —> NaCl + H₂O
From the balanced equation above,
The mole ratio of the acid, HCl (nA) = 1The mole ratio of the base, NaOH (nB) = 1From the question given above, the following data were obtained:
Volume of base, NaOH (Vb) = 50 mLConcentration of base, NaOH (Cb) = 0.1 MConcentration of acid, HCl (Ca) = 0.2Volume of acid, HCl (Va) =?CaVa / CbVb = nA / nB
(0.2 × Va) / (0.1 × 50) = 1
(0.2 × Va / 5 = 1
Cross multiply
0.2 × Va = 5
Divide both side by 0.2
Va = 5 / 0.2
Va = 25 mL (Option C)
2. How to determine the molarity of NaOHBalanced equation
H₂SO₄+ 2NaOH —> Na₂SO₄ + 2H₂O
From the balanced equation above,
The mole ratio of the acid, H₂SO₄ (nA) = 1The mole ratio of the base, NaOH (nB) = 2From the question given above, the following data were obtained:
Volume of base, NaOH (Vb) = 40 mLConcentration of acid, H₂SO₄ (Ca) = 1.5 MVolume of acid, H₂SO₄ (Va) = 15 mL Concentration of base, NaOH (Cb) =?CaVa / CbVb = nA / nB
(1.5 × 15) / (Cb × 40) = 1 / 2
22.5 / (Cb × 40) = 1 / 2
Cross multiply
Cb × 40 = 22.5 × 2
Divide both side by 40
Cb = (22.5 × 2) / 40
Cb = 1.13 M (Option A)
3. How to determine the molarity of HNO₃Balanced equation
HNO₃ + KOH —> KNO₃ + H₂O
From the balanced equation above,
The mole ratio of the acid, HNO₃ (nA) = 1The mole ratio of the base, KOH (nB) = 1From the question given above, the following data were obtained:
Volume of base, KOH (Vb) = 71.4 mLConcentration of base, KOH (Cb) = 4.2×10¯³ MVolume of acid, HNO₃ (Va) = 10 mL Concentration of acid, HNO₃ (Ca) =?CaVa / CbVb = nA / nB
(Ca × 10) / (4.2×10¯³ × 71.4) = 1
(Ca × 10) / 0.29988 = 1
Cross multiply
Ca × 10 = 0.29988
Divide both side by 10
Ca = 0.29988 / 10
Ca = 3×10¯² M (Option B)
Learn more about titration:
https://brainly.com/question/14356286
5. Which statement is NOT true?
a. Light travels with or without a medium.
b. Sound must have a medium to travel through.
c. Both light and sound must have a medium to travel through.
d. Light travels faster than sound.
Answer:
A: true.
B: true.
C: false
D: true.
Explanation:
Light is an electromagnetic wave which travels regardless of whether there is medium. sound is a wave disturbance in medium meaning it must have matter. Also light is much faster then sound.
If 7.0 mol sample of a gas has a volume of 12.2 L, what would the volume be if the amount of gas was increased to 16.8 mol
Answer:
[tex]V_{2} = 29.28\,L[/tex]
Explanation:
Let assume that gas behaves ideally and experiments an isobaric and isothermal processes. The following relationship is applied to determined the final volume:
[tex]\frac{V_{1}}{n_{1}} = \frac{V_{2}}{n_{2}}[/tex]
[tex]V_{2} = V_{1} \cdot \left(\frac{n_{2}}{n_{1}} \right)[/tex]
[tex]V_{2} = (12.2\,L)\cdot \left(\frac{16.8\,moles}{7\,moles} \right)[/tex]
[tex]V_{2} = 29.28\,L[/tex]
A sample of diborane gas has a pressure of 345 torr at a temperature of -15c and volume of 3.48L if conditions are changed so that the temperature is 36c and the pressure is 468 torr what will be the volume of the sample
Answer: 3.05L= V2
Explanation:
using
P1V1/T1=P2V2/T2
where p1= 345torr
T1, tempertaure= -15c+ 273=258K
T2, temperature= 36+ 273=309K
p2, Pressure= 468 torr
V2=???
P1V1/T1=P2V2/T2
v2=P1V1T2/T1P2= 345X3.46L X 309/ 258X 468=
V2= 3.05L
Name the following straight-chain Alkanes (picture)
Answer:
I don't know about the rest but A is heptane
1. Calculate the molarity of 35g of calcium chloride (CaCl2) that is dissolved in 850ml of water. (Calculate moles first)
a. 0.27M
b. 0.38M
c. 0.32M
d. 0.80M
2. Calculate the molarity of 90g of copper sulfate (CuSO4) when dissolved in 5 L of water.
a. 0.112M
b. 2.8M
c. 0.56M
d. 0.50M
3. What is the molarity of NaOH if 0.70 moles are dissolved in 250 ml of water?
a. 175,000M
b. 2.8M
c. 0.175M
d. 4M
4. How many moles of Lithium oxide (Li20) are in 2 L of solution with a molarity of 2.0M?
a. 1 mole
b. 2 moles
c. 0.2 moles
d. 4 moles
5. How many moles of NaCl are in 7.5 L of 0.5M?
a. 3.75 moles
b. 15 moles
c. 0.066 moles
d. 2.5 moles
Answer:
yo I got same question do u know it
Have scientists found any reliable predictors for earthquakes, like radon gas release or weird animal behavior?
Answer:
The "Parkfield earthquake prediction experiment" was the most heralded scientific earthquake prediction ever. It was based on an observation that the Parkfield segment of the San Andreas Fault breaks regularly with a moderate earthquake of about M 6 every several decades: 1857, 1881, 1901, 1922, 1934, and 1966.
Explanation:
this is the best I could come up with. luv u.
What is an oxidizing agent ?
Answer:
A substance that tends to bring about oxidation by being reduced and gaining electrons
Explanation:
Answer:
An oxidizing agent is a substance that takes negatively charged electrons "away" from a substance or object; usually taking these electrons for itself it can also transport the electrons from an object and "give" them to another substance or object. The object that has been oxidized will then have a positive charge after losing the negative electrons and the substance receiving the electrons will become negative.
Explanation:
Examples include halogens, potassium nitrate, and nitric acid.
