IGCSE chemistry periodic table

Front

What is the formula of the compound formed between astatine and hydrogen?

Back

HAt (Hydrogen Astatide)

Front

Balance the equation for the formation of sodium peroxide: Na + O2 -> ?

Back

2Na + O2 -> Na2O2

Front

Why do elements in group 7 have similar chemical reactions?

Back

They have the same number of outer electrons.

Front

Which group contains elements whose atoms form ions with a 2+ charge?

Back

Group 2.

Front

What color change is observed when bromine is added to an aqueous solution of potassium iodide?

Back

The solution turns brown.

Front

What are the main groups of the periodic table?

Back

Group 1 (Alkali metals), Group 2 (Alkaline earth metals), Group 3-12 (Transition metals), Group 13-16 (Post-transition metals, Metalloids, Nonmetals), Group 17 (Halogens), Group 18 (Noble gases).

Front

What is the general trend in reactivity for alkali metals as you move down the group?

Back

Reactivity increases down the group.

Front

What is the electron configuration of sodium (Na)?

Back

1s² 2s² 2p⁶ 3s¹.

Front

What is the significance of the atomic number?

Back

It represents the number of protons in an atom's nucleus.

Front

What is a covalent bond?

Back

A chemical bond formed by the sharing of electrons between atoms.