chemistry
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CHEMISTRY. MID TERM EXAM REVIEW. 1. 1. How many atoms of hydrogen are present in 3 moles of acetic acid?. 2. - PowerPoint PPT PresentationTRANSCRIPT
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1. How many atoms of hydrogen are present in 3 moles of acetic acid?
3 mol Ac x 4 moles H x 6.02 X 1023atoms H 1 mole Ac 1 mole H
= 7.22 X 1024atoms
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3. How many moles of carbon is present in 2 moles of butane?
2 mol butane x 4 mol C = 8 mol C 1 mol butane
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4. What is the percent composition of ethanol?First find MOLAR MASS2C = 2 x 12.0 = 24.06H = 6 x 1.0 = 6.01O = 1 x 16.0 = 16.0Total 46.0 g/mol
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4. - continued What is the percent composition of ethanol?
Mass of each element / Total x 100 = %
%C = 24.0/46.0 x (100) = 52% %H = 6.0/46.0 x (100) = 13%%O = 16.0/46.0 x (100) = 35%
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5. Classify the reactions shown below
Decomposition
Single replacement
Synthesis
Double replacement
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6. What number should be written in front of Na to balance
the equationNa + Cl2 NaCl ?
22Na + Cl2 2NaCl
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7. What number should be written in front of Fe in order to
balanceFe + O2 Fe2O3?
4 4Fe + 3O2 2Fe2O3
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8. Measure the object with the ruler to the correct number of significant figures. 11.65 cm
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8. Measure the object with the ruler to the correct number of significant figures. 11.65 cm
Must make ONE estimate smaller than marks.
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13. What is the formula for the compound that will form between calcium and phosphate ions?
Ca3(PO4)2
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16. In a chemical reaction, the total mass of the products compared to the total mass of the reactants is
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16. In a chemical reaction, the total mass of the products compared to the total mass of the reactants is
always the same
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17. Calculate the number of atoms in 1.40 mol of Ag.
1.40 mol x 6.02 X 10 23 atoms
1 mol
= 8.43 X 10 23 atoms
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21. In the formula 3 Mg(NO3)2, the total number of atoms is
18 oxygen atoms +
3 Mg atoms +
6 nitrogen atoms
= 27 total atoms
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24. What is the name of the Law that directs us to balance equations?
The Law of
Conservation of Matter
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25. When oxygen is available, nitrogen dioxide is produced from the burning of nitrogen. Write the word equation for this reaction.
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25. When oxygen is available, nitrogen dioxide is produced from the burning of nitrogen. Write the word equation for this reaction.
nitrogen + oxygen nitrogen dioxide
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25. When oxygen is available, nitrogen dioxide is produced from the burning of nitrogen. Write the word equation for this reaction.
oxygen + nitrogen nitrogen dioxide
also acceptable
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26. Give two examples of a chemical change.
Souring milk, burning anything, cooking, rotting, decaying leaves, releasing a gas, reacting to…
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27. Classify each of the following reactions:
2 Mg + O2 MgO
CH4 + O2 CO2 + 2 H2O
AgNO3 + NaCl NaNO3 + AgCl
H2O H2 + O2
AgCl + Cu CuCl + Ag
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27. Classify each of the following reactions:
2 Mg + O2 MgO synthesis
CH4 + O2 CO2 + 2 H2O combustion
AgNO3 + NaCl NaNO3 + AgCl double replacement
H2O H2 + O2 decomposition
AgCl + Cu CuCl + Ag single replacement
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28. Balance each of the following equations
a. NaCl Na + Cl2
b. S + Cl2 SCl3
c. K + AgCl Ag + KCl
d. Ca(OH)2 + HCl H2O + CaCl2
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28. Balance each of the following equations
a. 2 NaCl 2 Na + Cl2
b. 2 S + 3 Cl2 2 SCl3
c. K + AgCl Ag + KCl
d. Ca(OH)2 + 2 HCl 2 H2O + CaCl2
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29. Use the experiment shown in the figure to answer the questions
a. A gas was given off, collected in a test tube, and then tested with a burning splint. A “pop/chirp” was heard. What was the gas?
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29. Use the experiment shown in the figure to answer the questions
a. A gas was given off, collected in a test tube, and then tested with a burning splint. A “pop/chirp” was heard. What was the gas?
What are the reactants?
What type/classification of reaction?
What are products?
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29. Use the experiment shown in the figure to answer the questions
a. A gas was given off, collected in a test tube, and then tested with a burning splint. A “pop/chirp” was heard. What was the gas?
Mg + HNO3
single replacement
hydrogen + magnesium nitrate
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29. Use the experiment shown in the figure to answer the questions
a. A gas was given off, collected in a test tube, and then tested with a burning splint. A “pop/chirp” was heard. What was the gas?
hydrogen NOT the magnesium nitrate
ionic compounds are solids or dissolved (aq) in water
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29. Use the experiment shown in the figure to answer the questions
b. The substances Mg metal and dilute HNO3, are called --?
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29. Use the experiment shown in the figure to answer the questions
b. The substances Mg metal and dilute HNO3, are called --?
reactants
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29. Use the experiment shown in the figure to answer the questions
c. Write the correct balanced equation for the experiment