Chemistry help.. please easy 10 points?

Question

please help im kinda lost here..... thank you

Identify the following chemical equations by type.

1. How many grams of NaCl will be produced when 22.85 g of HCl are neutralized by an excess of NaOH according to the equation below? HCl + NaOH ---> H2O + NaCl

2. How many grams of potassium nitrate are required to produce 5.00 g of potassium nitrite according to the equation below? 2KNO3(s) ---> 2KNO2(s) + O2(g)

3. How many grams of magnesium oxide are produced when 10.00 grams of magnesium burn in an excess of oxygen, as shown below? 2Mg + O2 ---> 2MgO

4. How many grams of aluminum would react completely with 17.50 grams of copper (II) chloride according to the following equation? Al(s) + CuCl2(aq) ---> AlCl3(aq) + Cu(s)

Answer 1

Answers

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1. 36.8172 g (double replacement reaction)

2. 4.2555 g (decomposition reaction)

3. 22.591 g (combination reaction)

4. give a try (single replacement reaction)

Process

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1. the mole ratio of HCl : NaCl is 1:1

so the mole of HCl is the same as NaCl

moles of HCl = mass * molecular mass

= 22.85 / 36.46 (because H=1.01, Cl=35.45)

= 0.63 mol

mol of HCl = mol of NaCl

therefore mol of NaCl = 0.63 mol

mass of NaCl = 0.63 mol * 58.44 (because Na=22.99, Cl=35.45)

= 36.8172 g

2. the mole ratio of KNO3 : KNO2 is 2:2 = 1:1

so the mole of KNO3 is the same as NaCl

moles of KNO3 = mass * molecular mass

= 5.00 / 101.11 (because K=39.1, N=14.01,O=16.00)

= 0.05 mol

mol of KNO3= mol of KNO2

therefore mol of NaCl = 0.05 mol

mass of KNO2 = 0.05 mol * 85.11 (because K=39.1, N=14.01,O=16.00)

= 4.2555 g

4. the mole ratio of Mg : MgO is 2:2 = 1:1

so the mole of Mg is the same as MgO

moles of Mg = mass * molecular mass

= 10.00 / 24.31 (because Mg=24.31)

= 0.41 mol

mol of Mg= mol of MgO

therefore mol of MgO = 0.41 mol

mass of KNO2 = 0.41 mol * 55.1 (because Mg=39.1, O=16.00)

= 22.591 g