hgتارراتاترارتاتاتراتر

1. A reaction involves two substances as reactants and produces one compound. Which type of reaction is it likely to be?

• decomposition

• single-replacement

• synthesis

• double-replacement

t 2. What kind of reaction does the following generic equation represent?
A + BX -> AX + B

• double-replacement

• single-replacement

• synthesis

• decomposition

3. According to the activity series, which of the metals is most active?

• tin

• sodium

• lithium

• gold

4. Which of the following is NOT true about balancing chemical equations?

• Subscripts should never be changed to balance the equation

• Coefficients are written in their lowest possible ratio.

• Coefficients are changed to make the number of each element equal on both sides.

• Subscripts are changed to make the number of each element equal on both sides.

5. How many oxygen atoms are in 25 g of oxygen?

• 1.9 × 10^24 atoms

• 2.4 × 10^26 atoms

• 9.4 × 10^23 atoms

• 1.5 × 10^25 atoms

6. The following equation represent:

• Balanced equation

• Skeleton equation

• Word equation

• Combustion equation

7. In the following equation, Which of the following represent the reactants?
2NaOH + CaBr2 → Ca(OH)2 + NaBr

• NaOH and CaBr2

• NaOH and NaBr

• NaOH and Ca(OH)2

• Ca(OH)2 and NaBr

8. The equation that lacks information about the number of atoms involved is called:

• Balanced equation

• Skeleton equation

• Word equation

• B and C

9. The starting material in chemical equation is called:

• Reactants

• products

• Formed material

• Solids

10.What is numerically the same as the molar mass of an element?

• the atomic number of the element

• the atomic mass of the element

• the density of the element

• . the number of protons and electrons in the element