1. Mid Quarter 1 Test Review

2. How many protons, neutrons, and electrons are in an atom of 40Ar?
2.23) 18 p, 22 n, 18 e

3. What information can be derived from a mass spectrum for one particular element?
The number of isotopes, the mass of the isotopes, their relative abundance in the sample, and the average atomic mass can be calculated

4. Calculate the percent by mass of hydrogen in ascorbic acid, HC6H7O6.

5. How many hydrogen atoms are present in 1
How many hydrogen atoms are present in 1.00 mg of aspartame, C14H18N2O5?
3.38 d) x 1019 atoms H

6. CaH2 + 2H2O  Ca(OH)2 + 2H2 How many grams of calcium hydride are needed to form g of hydrogen?
3.62 b) g CaH2

7. Write the net ionic equation for the precipitation reaction between solutions of iron(II) nitrate and potassium hydroxide.
4.24 c) Fe2+(aq) + 2OH-(aq)  Fe(OH)2(s)

8. If 2 moles of solids were added to 100 mL of water, which of the following solutions would have the largest concentration of solvated protons? Explain. HI OR HF
HI; HI is a strong acid whereas HF is a weak acid. Thus, the strong acid fully dissociates, producing the maximum number of hydrogen ions. The weak acid remains primarily in the molecular form.

9. 3Fe(NO3)3 + 2Al  3Fe + 2Al(NO3)3 What is the substance reduced?
4.51 b) iron

10. 2HCl + Mg(OH)2  2H2O + MgCl2 What volume in mL of 0
2HCl + Mg(OH)2  2H2O + MgCl2 What volume in mL of M HCl is needed to neutralize 2.87 g of Mg(OH)2?
4.81 b) 769 mL

11. Menthol is composed on C, H, and O. A 0
Menthol is composed on C, H, and O. A g sample of menthol is burned in air producing g of carbon dioxide and g of water. Menthol’s molar mass is 156 g/mol. What is its molecular formula?
3.51 b) C10H20O empirical and molecular

12. A solid white substance A is heated strongly in the absence of air
A solid white substance A is heated strongly in the absence of air. It decomposes to form a new white substance B and a gas C. The gas has exactly the same properties as the product obtained when carbon is burned in an excess of oxygen. Based on these observations, can we determine whether solids A and B and the gas C are elements or compounds? Explain your conclusions.
1.15) C must be carbon dioxide as that is the product of carbon burned in air. Since A is heated in the absence of air (no oxygen), then A must have contained the element oxygen and carbon. B can not be determined definitively based on the information. However, few elemental solids are white.