S3 Chem Bk2 (U5-8)

We can obtain 2 volumes of hydrogen gas and 1 volume of oxygen gas from water by ____.

i.e. water( $H_2O$  ) ⎯____→ hydrogen + oxygen 

Such that hydrogen:oxygen=1:2

Suggest an element that is liquid in room temperature.

Which of the following is/are not good electrical conductor(s).

• Graphite

• Sodium

• Phosphorus

• Argon

What is the atomic symbol for Copper?

What is the atomic symbol for Gold?

What is the atomic symbol for iron?

What is the atomic symbol for lead

What is the atomic symbol for silver?

What are the electrical charge of electrons, protons and neutrons?

(+ve: positive; -ve: negative; =ve: neutral)

• Electrons: +ve; Protons: -ve, neutrons: =ve

• Electrons: -ve; Protons: +ve, neutrons: =ve

• Electrons: +ve; Protons: =ve, neutrons: -ve

• Electrons: =ve; +Protons: ve, neutrons: -ve

Which of the following atoms is the biggest in size?

• Helium

• Silicon

• Gold

• Iodine