Elements in Science for Grade 8

What is the smallest unit of an element?

• atom

• ion

• compound

• molecule

Which of the following is a noble gas?

• Nitrogen

• Carbon Dioxide

• Oxygen

• Helium

What is the chemical symbol for Gold?

• Au

• Pb

• Ag

• Fe

Which element is known as the 'building block of life'?

• Carbon

• Hydrogen

• Oxygen

• Nitrogen

What is the most abundant element in the universe?

• Oxygen

• Carbon

• Helium

• Hydrogen

Which of the following elements is a metal?

• Oxygen

• Iron

• Sulfur

• Carbon

What is the atomic number of Carbon?

• 7

• 12

• 5

• 6

Which element is essential for respiration in humans?

• Carbon Dioxide

• Oxygen

• Nitrogen

• Hydrogen

What is the main component of the Earth's atmosphere?

• Nitrogen

• Argon

• Carbon Dioxide

• Oxygen

Which of the following is a diatomic molecule?

• CO2

• N2O

• O2

• H2O