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<h3 align="center">CHM142 General Chemistry: Homework 1</h3>

**Question 1 (2 points):** A student thought that the mass of carbon must be 12 amu because he believed that carbon has 6 protons and 6 neutrons. However, he found on a periodic table of the elements that the mass of carbon is 12.011 amu. Why does this difference happen?

**Question 2 (8 points):** When hydrogen sulfide gas is bubbled into a solution of sodium hydroxide, the reaction forms sodium sulfide and water. How many grams of sodium sulfide are formed if 3.00 g of hydrogen sulfide is bubbled into a solution containing 10.00 g of sodium hydroxide, assuming that the sodium sulfide is made in 97.5% yield?

**Discussion is encouraged, but plagiarism is prohibited. Plagiarized part(s), if detected, receive zero points.**

<u>**Answer:**</u>