carbon

This factor contributes to the carbon cycle

•  fossil fuel combustion

• respiration

• Photosynthesis

• All of these

The source of carbon to plants in the carbon cycle is

• Fossil fuels

• Carbonate rocks

• Atmospheric carbon dioxide

• All of the answers

The role of bacteria in carbon cycle is

• to breakdown organic compound

• chemosynthesis

• photosynthesis

• none of the answers

In the carbon cycle, the human body returns carbon to the atmosphere through

• the formation of glucose

• the waste product

• photosynthesis

• cellular respiration

Electronic configuration for Carbon (C)

• 1s² 2s¹

• 1s2 2s2 2p2

• 1s¹ 2s¹

• 1s¹ 2s²

In which direction do electrons flow from the battery?

• Positive to positive terminal

• 1. Negative to negative terminal

• Negative to positive terminal

• Positive to negative terminal

What is the sign of the electron charge?

• 1. Positive 

• Negative

• 1. Neutral 

• None of these

Which of the following materials DOES NOT contain carbon?

• 1. Pencil lead 

• Pen

• Battery

• Metals

Carbon (C) consists of _______ valence electrons

• 4

• 3

• 6

• 7

The figure below shows the electron configuration of Carbon (C) atom. How many valence electrons are there?

• 2

• 3

• 6

• 4