Question

assess it! part 1

1. which is not true about all of these elements?

a. they are all in the same group
b. they all have the same number of valence electrons
c. they all have the same number of protons
d. they all share similar properties

1. which element has 2 valence electrons and is in period 4?

a. sodium
b. carbon
c. beryllium
d. calcium

1. which two elements share similar properties?

a. oxygen and sulfur
b. oxygen and nitrogen
c. oxygen and helium
d. oxygen and chlorine

Explanation:

1.

• Option A: Elements in the same group (column) in the periodic table. The given elements (O, S, Se, Te) are in group 16.
• Option B: Elements in the same group have the same number of valence electrons. Group 16 elements have 6 valence electrons.
• Option C: The number of protons (atomic number) is unique for each element. O has 8 protons, S has 16, Se has 34, Te has 52.
• Option D: Elements in the same group share similar properties.

• Period 4: The fourth row of the periodic table.
• 2 valence electrons: Group 2 elements have 2 valence electrons.
• Calcium (Ca): In period 4 and group 2.

• Elements in the same group share similar properties.
• Oxygen (O) and sulfur (S) are in group 16.

Answer:

C. They all have the same number of protons

2.