compound Formulas, reactions and balancing equations

Question 1

what does a formula tell you about its compound?

Answer 1

it tells you what the compound is made out of.

Question 2

what do the brackets in a compound formula mean?

Answer 2

everything inside the brackets is multiplied by the number immediately after the last bracket.

Question 3

during a chemical reaction none of the atoms…

Answer 3

disappear or appear. you are always left with the same amount as you started with. They are just arranged differently.

Question 4

the mass of reactants is always equal to the mass of…

Answer 4

the products. (because atoms are not gained or lost in the reaction)

Question 5

Balance the following equation:

__ SnO2 + __ H2 → __ Sn + __ H2O

Answer 5

1 SnO2 + 2 H2 → 1 Sn + 2 H2O

Question 6

Balance the following equation:

__ KOH + __ H3PO4 → __ K3PO4 + __ H2O

Answer 6

3 KOH + 1 H3PO4 → 1 K3PO4 + 3 H2O

Question 7

Balance the following equation:

__ KNO3 + __ H2CO3 → __ K2CO3 + __ HNO3

Answer 7

2 KNO3 + 1 H2CO3 → 1 K2CO3 + 2 HNO3

Question 8

Balance the following equation:

__ Na3PO4 + __ HCl → __ NaCl + __ H3PO4

Answer 8

1 Na3PO4 + 3 HCl → 3 NaCl + 1 H3PO4

Question 9

Balance the following equation:

__ TiCl4 + __ H2O → __ TiO2 + __ HCl

Answer 9

1 TiCl4 + 2 H2O + 1 TiO2 + 4 HCl

Question 10

Balance the following equation:

__ C2H6O + __ O2 → __ CO2 + __ H2O

Answer 10

1 C2H6O + 3 O2 → 2 CO2 + 3 H2O

Question 11

Balance the following equation:

__ Fe + __ HC2H3O2 → __ Fe(C2H3O2)3 + __ H2

Answer 11

2 Fe + 6 HC2H3O2 → 2 Fe(C2H3O2)3 + 3 H2

Question 12

Balance the following equation:

__ NH3 + __ O2 → __ NO + __ H2O

Answer 12

4 NH3 + 5 O2 → 4 NO + 6 H2O

Question 13

Balance the following equation:

__ B2Br6 + __ HNO3 → __ B(NO3)3 + __ HBr

Answer 13

1 B2Br6 + 6 HNO3 → 2 B(NO3)3 + 6 HBr

Question 14

Balance the following equation:

__ NH4OH + __ Kal(SO4)2·12H2O → __ Al(OH)3 + __ (NH4)2SO4 + __ KOH + __ H2O

Answer 14

4 NH4OH + 1 Kal(SO4)2·12H2O → 1 Al(OH)3 + 2 (NH4)2SO4 + 1 KOH + 12 H2O