Choose the letter of the best answer. Write the chosen letter on a separate sheet
of paper.
1. Which element can conduct heat and electricity?
A. iodine
B. copper
C. carbon
D. fluorine
2. Which substance is used as pencil lead?
a. potassium
b. iron
c. carbon
d. nickel
3. Which the most abundant element found in earth's crust and human
body?
a. hydrogen
b. oxygen
c. nitrogen
d. silicon
4. Which compound is used as preservative and food sweetener?
a. baking soda
b. sodium chloride
C. sucrose
d. calcium carbonate
5. Which substance is used in soap making?
a. calcium carbonate (CaCO3)
b. sodium hydroxide (NaOH)
c. sulfuric acid (HCI)
d. nitric acid (HNO3)​