1

Sam is studying the position of an unknown element in the periodic table. He determines that the element has an electronic configuration of 2,8,7. In which group and period is this element?

2

Which of the following is a physical property?

3

Ethan is learning about polar and non-polar molecules. He knows that polar molecules have a dipole moment. Which of the following molecules is non-polar?

4

Tina is studying the disadvantages of metals in water. She knows that certain metals are toxic. Which of the following is a toxic metal that can contaminate water?

5

Which bond results in formation of ions?

6

Dissolved oxygen in water is essential for:

7

Patricia is studying weak bases. She knows that weak bases have low dissociation in water. Which of the following is a weak base?

8

In NaCl, sodium atom:

9

Patricia is exploring ionic equations. She writes the complete ionic equation for a reaction. What is the difference between a molecular equation and an ionic equation?

10

Which branch explains energy changes and reaction rates?

11

Xia is studying the effects of climate change. She understands that climate change affects food production. How does climate change affect agriculture?

12

Vera is studying how solar energy can be harnessed. She learns about photovoltaic cells that convert sunlight into electricity. Which branch of chemistry is involved in developing photovoltaic materials?

13

Which vitamin group is called B-complex?

14

Nadia is studying allergens. She learns that allergens can trigger allergic reactions. Which of the following is an example of an outdoor allergen?

15

Which layer of atmosphere is important for radio communication?

16

Hina is studying ionization energy. She knows that ionization energy is the energy required to remove an electron from a gaseous atom. As we move across a period from left to right, ionization energy generally:

17

Julia is learning about the basic components of food. She understands that nucleic acids are found in all living cells. Which food is a source of nucleic acids?

18

Which phase moves during chromatography?

19

Sam is studying a gas that is found in neon signs. The gas glows when electricity passes through it. This state of matter is called:

20

Ahmed is collecting data on the pH of different solutions. He uses a pH meter to measure the pH. What type of data is pH measurement?

21

Which bond is formed by sharing of electrons?

22

Ionic bond is usually formed between:

23

Allotropes are different forms of:

24

Astrochemistry studies chemicals in:

25

Which quantity is conserved in a chemical reaction?