WorksheetsUnit 5 Practice Quiz 1
Total questions: 15
Worksheet time: 10mins
Moles are a unit that we use to measure
The volume of a sample
The number of particles in a sample
The mass of a sample
The density of a sample
We must determine the moles in a sample by measuring the mass of the sample and converting the mass to moles. This is because . . . .
mass values are more accurate than mole values.
the periodic table gives us molar mass values.
atoms and molecules are too small to count directly.
the mass of the material is related to its density while the number of moles is not.
Choose the true statement
For nearly any sample, the number of grams will be bigger than the corresponding number of moles.
For some samples, the number of grams is bigger than the corresponding number of moles. For others, the reverse is true.
For nearly all samples, the number of moles is at least as big as the corresponding number of grams.
None of the above statements are true.
Choose the best reason that moles are important in chemistry
The greater the number of moles in a sample, the greater the density of the sample.
Moles are more accurate than grams
The amount of moles in a sample is related to the chemical reactivity of the sample.
Atoms and ions combine with each other based on how many of them are involved, not on their masses.
"For any substance, the greater the mass, the greater the corresponding number of moles." This statement is . . .
always true
sometimes true
rarely true
never true
"If substance A has a greater molar mass than substance B, then the moles in a sample of A will always be greater than the moles in a sample of B" This statements is . . .
Always True
Usually true
Sometimes true
Irrelevant
"Substance A has a large molar mass and substance B has a small molar mass. If I have the same mass of A as B, the B sample will contain more moles." This statement is . . .
Always true
Usually true
Sometimes true
Never true
In 0.30 moles of HClO4, how many moles of oxygen atoms are there?
0.30 mol
1.20 mol
1.50 mol
0.075 mole
In 1 mole of octane molecules, C8H18, the total number of moles of atoms is . . .
1
8
18
26
If a sample contains 0.80 moles of methane molecules (CH4), the number of moles of carbon atoms is . . .
0.80
3.2
4.0
0.20
To the nearest whole number, the molar mass of water is (a) g/mole
To the nearest whole number, the molar mass of HBr is (a) g/mole.
To the nearest whole number, the molar mass of ethanol, C2H5OH, is (a) g/mole.
To the nearest whole number, the molar mass of octane, C8H18, is (a) g/mole
To the nearest whole number, the molar mass of sucrose (table sugar -- C12H22O11) is (a) g/mole
