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Moles
Percent Comp
Reaction Types/More Balancing
Misc
100

A student has one mole of an element in a beaker. The mass, excluding the beaker, is 237 g? What is the element?

Neptunium

100

Calculate the percent composition of potassium KMnO4.

25% K

100

Balance and classify: 

__N2O5 + __H2O ->  __HNO3

N2O5 + H2O ->  2HNO3  synthesis

100

How many moles are in 26 g of carbon?

2.16 mol

200

What is the mass of one mole of butane (C4H10)? Don't forget units!

58.14 g/mol

200

What is the percent composition of oxygen in Ca(OH)2?

43%O

200

Balance and classify

__KClO3 -> __KClO4 + __ KCl

4KClO3 -> 3KClO4 + KCl decomposition

200

What is the mass of one mole of C2H3O4?

91.05 g/mol

300

What is the mass of 2.5 mol of NaCl?

146.1 g

300

Calculate the percent composition of each element in (NH4)3PO4.

21% P, 43%O, 28%N, 8%H

300

__Al + __Mg(ClO4)2 -> __Al(ClO4)3 + __ Mg

2Al + 3Mg(ClO4)2 -> 2Al(ClO4)3 + 3Mg single replacement

300

Write and balance the equation: 

Potassium + fluorine -> potassium fluoride

2K + F2 -> 2KF

400

How many moles are in 547 g of Ba(NO2)3?

1.99 mol

400

A sample of octane contains 96 g of carbon and 18 g of hydrogen.

What is the percent composition of each element in the compound?

84% C, 16% H

400

Balance and classify: 

__Al2(SO4)3 + __Ca(OH)2 -> __Al(OH)3 + __ CaSO4

Al2(SO4)3 + 3Ca(OH)2 -> 2Al(OH)3 + 3 CaSO4  double replacement

400

Calculate the mass of 0.5 moles of hydrogen sulfate. 

49.05 g

500

How many moles are there in 3.25 x 1024 atoms of potassium?

5.4 mol

500

A 38.90g sample of a carbon-oxide compound contains 10.18g of carbon.  

What is the percent composition of carbon and the percent composition of oxygen in the compound?

26%C, 74%O

500

Balance and classify: 

__ C2H2 + __O2 -> __CO2 + __H2O

2 C2H2 + 5O2 -> 4CO2 + 2H2O  combustion

500

Write and balance the equation: 

Nitrogen trihydride + oxygen -> nitrogen + dihydrogen monoxide

4NH3 + 3O2 -> 2N2 + 6H2O