91Ó°ÊÓ

A chemist decomposes \(1.006 \mathrm{~g}\) of \(\mathrm{NaHCO}_{3}\) and obtains \(0.0334 \mathrm{~g}\) of \(\mathrm{Na}_{2} \mathrm{CO}_{3}\). What are the theoretical yield and the actual yield? $$ 2 \mathrm{NaHCO}_{3}(\mathrm{~s}) \rightarrow \mathrm{Na}_{2} \mathrm{CO}_{3}(\mathrm{~s})+\mathrm{H}_{2} \mathrm{O}(\ell)+\mathrm{CO}_{2}(\mathrm{~g}) $$

How many moles are present in \(3.55 \times 10^{24} \mathrm{~Pb}\) atoms?

Given the chemical equation $$ \mathrm{Na}(\mathrm{s})+\mathrm{H}_{2} \mathrm{O}(\ell) \rightarrow \mathrm{NaOH}(\mathrm{aq})+\mathrm{H}_{2}(\mathrm{~g}) $$ a) Balance the equation. b) How many molecules of \(\mathrm{H}_{2}\) are produced when 332 atoms of Na react?

For the chemical equation \(2 \mathrm{C}_{2} \mathrm{H}_{6}+7 \mathrm{O}_{2} \rightarrow 4 \mathrm{CO}_{2}+6 \mathrm{H}_{2} \mathrm{O}\) what equivalences can you write in terms of moles? Use the \(\Leftrightarrow\) sign.

Ethane \(\left(\mathrm{C}_{2} \mathrm{H}_{6}\right)\) is formed by reacting \(7.08 \mathrm{~g}\) of \(\mathrm{C}\) and \(4.92 \mathrm{~g}\) of \(\mathrm{H}_{2}\) \(2 \mathrm{C}(\mathrm{s})+3 \mathrm{H}_{2}(\mathrm{~g}) \rightarrow \mathrm{C}_{2} \mathrm{H}_{6}(\mathrm{~g})\).

How many moles of \(\mathrm{HCl}\) can be produced from \(0.226 \mathrm{~g}\) of \(\mathrm{SOCl}_{2}\) ? \(\mathrm{SOCl}_{2}(\ell)+\mathrm{H}_{2} \mathrm{O}(\ell) \rightarrow \mathrm{SO}_{2}(\mathrm{~g})+2 \mathrm{HCl}(\mathrm{g})\)

Given the chemical equation \(\mathrm{S}(\mathrm{s})+\mathrm{O}_{2}(\mathrm{~g}) \rightarrow \mathrm{SO}_{3}(\mathrm{~g})\) a) Balance the equation. b) How many molecules of \(\mathrm{O}_{2}\) are needed when 38 atoms of S react?

For the chemical equation \(2 \mathrm{Al}+3 \mathrm{Cl}_{2} \rightarrow 2 \mathrm{AlCl}_{3}\) what equivalences can you write in terms of moles? Use the \(\Leftrightarrow\) sign.

How many moles are present in \(2.09 \times 10^{22} \mathrm{Ti}\) atoms?

How many moles of \(\mathrm{O}_{2}\) are needed to prepare \(1.00 \mathrm{~g}\) of \(\mathrm{Ca}\left(\mathrm{NO}_{3}\right)_{2}\) ? \(\mathrm{Ca}(\mathrm{s})+\mathrm{N}_{2}(\mathrm{~g})+3 \mathrm{O}_{2}(\mathrm{~g}) \rightarrow \mathrm{Ca}\left(\mathrm{NO}_{3}\right) 2(\mathrm{~s})\)