Question

Use the periodic table to answer the question.

An illustration shows the periodic table of elements with elements arranged in increasing order of atomic number in 18 columns (groups) and 7 rows (periods).

Based on patterns in the periodic table, which list shows the acids in order from strongest conjugate base to weakest conjugate base?

(1 point)
Responses

H2Se, BrH, AsH3
H 2 Se, BrH, AsH 3

AsH3, H2Se, BrH
AsH 3 , H 2 Se, BrH

H2Se, AsH3, BrH
H 2 Se, AsH 3 , BrH

BrH, H2Se, AsH3

Answer 1

To determine the order of acids from strongest conjugate base to weakest conjugate base, we first need to understand the relationship between the strength of the acid and the strength of its conjugate base. Stronger acids have weaker conjugate bases.

1. **HBr (Hydrobromic acid)** is a strong acid, and its conjugate base is **Br⁻** (bromide ion). Since it is a strong acid, **Br⁻** is a weak conjugate base.

2. **H₂Se (Selenic acid)** is a weaker acid than HBr, hence its conjugate base (Se²⁻) will be stronger than Br⁻.

3. **AsH₃ (Arsenic acid)** is even weaker than H₂Se, meaning its conjugate base (As³⁻) will be stronger than Se²⁻.

Now we can arrange the acids based on the strength of their conjugate bases from strongest to weakest:

- **H₂Se -> Se²⁻** (conjugate base is a bit stronger)
- **BrH -> Br⁻** (conjugate base is very weak)
- **AsH₃ -> As³⁻** (conjugate base is stronger than the others)

In terms of order of conjugate base strength (strongest to weakest), we get:

1. \( \text{H}_2\text{Se} \) (second strongest)
2. \( \text{BrH} \) (weakest)
3. \( \text{AsH}_3\) (strongest)

Thus, the correct order from strongest conjugate base to weakest conjugate base is:

**BrH, H2Se, AsH3**

So the answer is:

**BrH, H2Se, AsH3**.