Compound Calculations

3.0 moles of chlorine are reacted with 3.0 sodium, what was the theoretical yield (how much NaCl should have been produced)?

• 6.0 mol NaCl

• 3.0 mol NaCl

• 9.0 mol NaCl

• 1.5 mol NaCl

Tags

NGSS.HS-PS1-7

If the theoretical yield is 18 moles and the actual yield is 14 moles, what is the percent yield?

• 128.6%

• 32.0%

• 77.8%

• 92.4%

What percentage of the total atomic mass of carbon monoxide (CO) is composed of oxygen?

• 29%

• 43%

• 57%

• 73%

What percentage of the total atomic mass of lithium phosphide (Li₃P) is composed of phosphorus?

• 13%

• 29%

• 40%

• 60%

Tags

NGSS.MS-PS1-1

What is the percent composition by mass of sulfur in the compound MgSO₄ (gram formula mass = 120 g/mol)?

• 20%

• 27%

• 46%

• 53%

The Law of Definite Proportions, proposed by Proust, states that:

• Elements are composed of small, indivisible particles called atoms.

• All samples of a given compound have the same elements in the same proportion by mass.

• Atoms of different elements can combine in simple, whole-number ratios to form compounds.

• The volume of a gas is directly proportional to the number of moles of gas present.

Tags

NGSS.HS-PS1-7

How much force is needed to accelerate a 3kg skateboard at 5m/s^2. 

• 8N

• 1.6N

• 0.6N

• 15N

Tags

NGSS.HS-PS2-1

A 50 kg skater pushed by a friend accelerates 5 m/s².  How much force did the friend apply? The answer to this question is most likely (HINT: Look at the units!!!) - 

• 250 N

• 250 m/s²

• 250 kg 

Tags

NGSS.HS-PS2-1

If 4.0 moles of hydrogen gas react with 2.0 moles of oxygen gas, what is the theoretical yield of water (H2O) produced?

• 4.0 mol H2O

• 2.0 mol H2O

• 8.0 mol H2O

• 6.0 mol H2O

Tags

NGSS.HS-PS1-7

What is the percent composition by mass of carbon in carbon dioxide (CO2)?

• 27%

• 33%

• 44%

• 50%