The answer is b but you want to think of why it is moving fast because of the temp indication
The answer is 159.69 g/mol
The symbols for three different cations with 14 protons are Si²⁺, Si⁴⁺, and Si³⁺.
An element with 14 protons must be <em>silicon, S</em>i.
Its electron configuration is [Ne] 3s²3p², so it could lose up to four valence electrons.
The most likely cations are Si²⁺, Si⁴⁺, and Si³⁺ (or Si⁺).