Chemistry Past Questions and Answers

10cm<sup style='font-size: smaller;'>3</sup> of hydrogen fluoride gas react with 5cm<sup style='font-size: smaller;'>3</sup> of dinitrogen difluoride gas (N<sup style='font-size: smaller;'>2</sup>F<sub style='font-size: smaller;'>2</sub>) to form 10<sub style='font-size: smaller;'>3</sub> of a single gas. Which of the following is the most likely equation of the reaction?

The number of atoms of chlorine present in 5.85g of NaCl is [Avogaro's Number = 6.02 x 10<sup style='font-size: smaller;'>23</sup>]

How much of magnesium is required to react with 260cm<sup style='font-size: smaller;'>3</sup> of 0.5 M HCl? [Mg = 24]

The relationship between the velocity (U) of gas molecules and their relative molecular mass (M) is shown by the equation

An element with atomic number twelve is likely to be