8 g of sodium hydroxide is dissolved in 2 dm 3 of water. Calculate the concentration of the sodium hydroxide solution formed. concentration = \(\frac{\textup{mass~of~solute~in~g}}{\textup{volume ...

\({\%~of~an~element} = \frac{mass~of~an~element~in~the~compound}{relative~formula~mass~M_r} \times 100\) There are six atoms of hydrogen in the compound, so the mass of hydrogen is 6 × 1 = 6.