What quantities are conserved in chemical reactions?

grams and atoms

What quantities are not conserved in chemical reactions?

liters and moles

When calculating percent yield, actual yield and theoretical yield are always ____________ of the same ____________.

grams, product

How many moles of Ca(OH) 2.35 moles of Al reaction?

2 (SO 4 ) 3 2 are needed to react completely with according to the following balanced chemical Al 2 (SO 4 ) 3 + 3Ca(OH) 2  2Al(OH) 3 + 3CaSO 4 7.05 moles Ca(OH) 2

Using the following balanced equation, calculate the number of grams of water formed when 0.75 moles of B(OH) 3 are used in the reaction.

3 H 2 SO 4 + 2 B(OH) 3  B 2 (SO 4 ) 3 + 6H 2 O 40.54 g H 2 O

How many moles of MgO form from the reaction below if enough reactants are used to form 15.98 g of Fe?

3 Mg + Fe 2 O 3  2 Fe + 3 MgO 0.43 mol MgO

Using the following equation: Pb(SO 4 ) 2 + 4 LiNO 3  Pb(NO 3 ) 4 + 2 Li 2 SO 4 How many grams of lithium nitrate will be needed to make 250 grams of lithium sulfate, assuming that you have an adequate amount of lead (IV) sulfate to do the reaction?

313.58 g LiNO 3

How many liters of NH (NH 4 ) 2 CO 3 balanced equation?

3 at STP form when 15.23 g of ammonium carbonate, , decompose according the following (NH 4 ) 2 CO 3  H 2 O + 2NH 3 + CO 2 7.10 L NH 3

Calcium carbonate decomposes to form carbon dioxide and calcium oxide: CaCO 3

(s)

 CO 2 (g) + CaO(s) How many grams of calcium carbonate will I need to form 3.45 liters of carbon dioxide at STP?

15.42 g

Ethylene burns in oxygen to form carbon dioxide and water vapor: C 2 H 4 (g) + 3 O 2

(g)

 2 CO 2 (g) + 2 H substances are at the same temperature and pressure.

2 O(g) How many liters of water vapor can be formed if 1.25 liters of ethylene are consumed in this reaction? Assume all 2.50 L H 2 O

Calculate the following: a) Which of the reagents is the limiting reagent?

b) How many grams of each product are formed?

c) How many grams of excess reactant remain?

3 NH 4 NO 3 + Na 3 PO 4  (NH 4 ) 3 PO 4 + 3 NaNO nitrate and 50 grams of sodium phosphate.

3 Assume we started with 30 grams of ammonium a) b) c) ammonium nitrate 18.6 grams of ammonium phosphate, 31.9 grams of sodium nitrate 29.5 grams of sodium phosphate

If the percent yield of the following equation is 55%, how many grams of H 2 SO 4 are produced when 44.8 L of SO 3 are combined with excess water? Assume the reaction occurs at STP. SO 3 (g) + H 2 O(l) → H 2 SO 4

(aq)

107.89 g H 2 SO 4

A 2.00 g sample of ammonia is mixed with 4.00 g of oxygen. Which is the limiting reactant and how many grams of excess reactant remains after the reaction has stopped? 4 NH 3 (g) + 5 O 2

(g)

 4 NO(g) + 6 H 2 O(g) oxygen, 0.30 g NH 3

90.0 g of FeCl 3 reacts with 52.0 g of H 2 2FeCl S, according to the following balanced equation: 3 + 3H 2 S  Fe 2 S 3 + 6HCl What is the limiting reactant? What is the mass of HCl produced? What mass of excess reactant remains after the reaction?

FeCl 3 , 60.8 g HCl, 23.6 g H 2 S

If 12.0 mL of 1.34 M NaOH is required to neutralize 25.00 mL of a sulfuric acid, H H 2 SO 4 2 SO 4 , solution, what is the molarity of the sulfuric acid?

The balanced titration reaction is (aq) + 2NaOH(aq)  Na 2 SO 4 (aq) + 2HOH(l).

0.322 M H 2 SO 4

What volume (in mL) of 0.075 M HCl is required to neutralize 100 mL of 0.01 M Ca(OH) 2 solution? The balanced titration reaction is 2HCl + Ca(OH) 2  2H 2 O + CaCl 2 .

26.7 mL HCl