International General Certificate of Secondary Education (IGCSE) Chemistry Practice Exam

Which element would typically have a higher reactivity with acids?

1. Sodium

2. Gold

3. Carbon

4. Bromine

The correct answer is: Sodium

Sodium is known for its high reactivity, especially with acids, due to its position in the alkali metals group of the periodic table. Alkali metals such as sodium readily lose their outermost electron, resulting in the formation of cations. When sodium reacts with acids, it produces hydrogen gas and a corresponding salt. This reaction is vigorous and can release a lot of heat, characterizing sodium's strong reactivity. In contrast, elements like gold are much less reactive. Gold is a noble metal and does not readily react with acids or many other substances, which is why it is often used in jewelry and electronics for its stability. Similarly, carbon, while it can react under certain conditions, does not exhibit the same level of reactivity with acids as sodium. Bromine, being a halogen, can react with acids, but its reactivity is still not as pronounced as that of alkali metals. Thus, sodium is the element that typically showcases higher reactivity with acids compared to the others listed.