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can someone double check my chem answers?

this is my final chem assignment. it would be nice if someone could check my answers.

Classify the chemicals in the list in compounds, ions, elements or mixtures. Write the molecular formulas of compounds, ions and elements. Suggest components of the mixtures.

1. Deionised Water
2. Carbon
3. Bronze
4. Milk
5. Chlorine
6. Ammonia
7. Sulphuric Acid
8. Sodium Nitrate
9. Bromine
10. Air
11. Copper Sulphate
12. Hydroxide
13. Mud
14. Petrol
15. Methane
16. Ethanol
17. Sodium Bicarbonate
18. Ammonium
19. Tin
20. Vinegar

Compounds
Deionised water: H2O
Ammonia: NH3
Sulphuric acid: H2SO4
Sodium nitrate: NaNO3
Copper sulphate: CuSO4
Methane: CH4
Ethanol: C2H5OH
Sodium bicarbonate: NaHCO3

Ions
Hydroxide: OH
Ammonium: NH4+

Elements
Carbon: C
Chlorine: Cl2
Bromine: Br2
Tin: Sn

Mixtures
Bronze: Bronze is a mixture of nine parts copper to one part tin.

Milk: The main components of milk are water, lipids, carbohydrates, proteins, vitamins and minerals. (www.preservearticles.com)

Air: Air is a combination of nitrogen (78.084%), oxygen (20.947%), argon (0.934%), carbon dioxide (0.0314%) and other gasses. (www.chemistry.about.com)

Mud: There are many types of soil, but the main components are a combination of sand, clay, silt, water and various types of organic matter such as bacteria.

Petrol: Petrol is a mixture of paraffin, napthene and olefin. Petrol contains a large mixture of hydrocarbons. (www.uk.ask.com)

Vinegar: Vinegar is made from fermenting ethanol. Its main ingredient is acetic acid although there may be other acids present such as tartaric and citric. (www.wisegeek.com)

Write properly balanced equations for the following reactions. State the molar ratios of the reactions.

Sodium Hydroxide + Phosphoric Acid
3NaOH + H3PO4 → Na3PO4+3H2O
Molar ratio =3:1

Methane + Oxygen
CH4 + 2O2 → CO2 + 2H2O
Molar ratio = 2:1

Zinc + Sulphuric Acid
Zn + H2SO4 → ZnSO4 + H2
Molar ratio= 1:1

Ammonia + Hydrochloric Acid
NH3 + HCl → NH4Cl + H2O
Molar ratio = 3:1

Sodium bicarbonate + Phosphoric Acid
H3PO4 + 3NaHCO3 → Na3PO4 + 3CO2 + 3H2O
Molar ratio = 3:1

Potassium + Iron (II) Sulphate
really not sure about this one ???

Iron + Hydrochloric Acid
Fe + 2HCl → FeCl2 + H2
Molar ratio = 2:1

Nitric Acid + Magnesium Hydroxide
2HNO3 + Mg(OH)2 → Mg(NO3)2 + 2H2O
Molar ratio = 2:1

Calculate the molecular weights of the following compounds

CuNO3 = 125.551 g/mol
KOH = 56.105 g/mol
Fe = 55.845 g/mol
H3PO4 = 97.995 g/mol
CO2 = 44.009 g/mol
CH4 = 16.042 g/mol
Na2SO4 = 142.042 g/mol
LiOH = 23.948 g/mol
Ca3(PO4)2 = 310.176 g/mol

In a neutralization reaction 5 gr of potassium nitrate are produced after complete consumption of the acid and base reactants. How many moles of acid and base were used?

To make 5g of KNO3 the following reaction must take place;

HNO3 + KOH → KNO3 + H2O

Code:

Formula HNO3 + KOH → KNO3 + H2Omw 63.01 56.10 101.10 18.10mass 3.116g 2.774g 5g 0.895gn 0.049 0.049 0.049 0.049

Ethanol burns according to the following reaction

C2H5OH (l) + 3 O2 (g) → 2 CO2 (g) + 3 H2O (g)

How many grams of reactants are required to produce 15 gr of water as a result of the reaction. (Note: Assume that the reaction was complete).

Code:

Formula C2H5OH + 3 O2 → 2 CO2 + 3 H2Omw 46.06 32 44 18mass 12.8g 26.6g 24.5g 15gn 0.278 0.833 0.556 0.833

After a complete reaction of sodium bicarbonate and hydrochloric acid the resulting gas was collected in a 2 lt container. The pressure exerted at the walls of the tank was 2000 KPa and
the temperature of the container was 300 K. Predict the amounts of reactants in gr.

NaHCO3 + HCl → NaCl + H2O + CO2

NaHCO3 = 134.7456g
HCl = 1.604g

Sea water contains about 0.50 moles per litre NaCl. To produce Cl2 gas, a company evaporates sea water, melts the NaCl, and runs electricity through it according to the reaction.

2 NaCl → 2 Na + Cl2

How many liters of sea water are needed to fill a tank car with 1,120,000 liters of chlorine gas at STP?

We would need 186238.124l of sea water

A complete reaction of zinc with hydrochloric acid produces 2,000 Lt of hydrogen at STP. How many grams of zinc and hydrochloric were required?
5435.824g of Zn
6062.897g of HCl

15 ml of 0.2 M NaOH react completely with 30 ml of HCl. What is the concentration of acid
0.1m

If 50 ml of 0. 5M KOH is required for neutralization of 125 ml sulphuric acid, what is the concentration of the acid?
0.1m

Calculate the empirical formula for a compound that has 108 g of aluminum and 426 g of chlorine.
AlCl3

If a compound is 47.3% C (carbon), 10.6% H (hydrogen) and 42.0% S (sulfur) by mass, what is its empirical formula?
C3H8S

Bromoethane can be produced from the reactants ethene (ethylene) and hydrogen bromide according to the following reaction:
C2H4 + HBr → C2H5Br
Calculate the % atom economy of the reaction.

atom economy = 100%

For the balanced equation shown below, if the reaction of 0.112 grams of H2 produces 0.745 grams of H2O, what is the percent yield?
Fe3O4 + 4H2 → 3Fe + 4H2O

73.2% yield

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