反應性2.1—有多少？化學變化的量：練習題

When \( 5.00 \text{ g} \) of sulfur is burned in excess oxygen, what is the maximum mass of sulfur dioxide, \( SO_2 \), produced?

\( S(s) + O_2(g) \rightarrow SO_2(g) \)

(Relative atomic masses: \( S = 32.06, O = 16.00 \))

A sample of gas occupies \( 2.0 \text{ dm}^3 \) at \( 300 \text{ K} \) and \( 100 \text{ kPa} \). What will be its volume at \( 600 \text{ K} \) and \( 50 \text{ kPa} \)?

A \( 2.50 \text{ g} \) sample of an unknown gas occupies \( 1.20 \text{ dm}^3 \) at \( 298 \text{ K} \) and \( 101.3 \text{ kPa} \). What is the molar mass of the gas?

(Gas constant \( R = 8.31 \text{ J K}^{-1} \text{mol}^{-1} \))

When \( 2.0 \text{ mol} \) of methane, \( CH_4 \), is burned in excess oxygen, what is the maximum amount, in moles, of water produced?

\( CH_4(g) + 2O_2(g) \rightarrow CO_2(g) + 2H_2O(l) \)

A compound contains \( 40.0\% \) carbon, \( 6.7\% \) hydrogen, and \( 53.3\% \) oxygen by mass. What is its empirical formula?

(Relative atomic masses: \( C = 12.01, H = 1.01, O = 16.00 \))

A solution of sodium chloride is prepared by dissolving $$5.85 \text{ g}$$ of $$NaCl$$ in water to make a final volume of $$250 \text{ cm}^3$$. Calculate the concentration of the $$NaCl$$ solution in $$mol \text{ dm}^{-3}$$. (Molar mass of $$NaCl = 58.44 \text{ g mol}^{-1}$$)