Question

instructions: in each question, list the elements from least to greatest atomic mass:

1. magnesium (mg), beryllium (be), barium (ba)
2. gallium (ga), selenium (se), potassium (k)
3. tellurium (te), arsenic (as), calcium (ca)

Explanation:

Step1: Recall atomic masses

Find atomic masses of elements:

• \(Be = 9.012\)
• \(Mg=24.305\)
• \(Ba = 137.327\)

Step2: Compare and order

Since \(9.012<24.305<137.327\)

Step1: Recall atomic masses

Find atomic masses of elements:

• \(K = 39.098\)
• \(Ga=69.723\)
• \(Se = 78.971\)

Step2: Compare and order

Since \(39.098<69.723<78.971\)

Step1: Recall atomic masses

Find atomic masses of elements:

• \(Ca = 40.078\)
• \(As=74.922\)
• \(Te = 127.60\)

Step2: Compare and order

Since \(40.078<74.922<127.60\)

Answer:

\(Be\), \(Mg\), \(Ba\)