MgBr2(aq) is an ionic compound which will have the releasing of 2 Br⁻ ions ions in water for every molecule of MgBr2 that dissolves. 
MgBr2(s) --> Mg+(aq) + 2 Br⁻(aq)
            [Br⁻] = 0.51 mol MgBr2/1L × 2 mol Br⁻ / 1 mol MgBr2 = 1.0 M
The answer to this question is [Br⁻] = 1.0 M
        
             
        
        
        
Do you have Answer Choices
        
             
        
        
        
Nope. It is false. Temperature decreases as altitude increases.
        
             
        
        
        
6.022×10^23 should be correct. Are there any options to choose from?
<u>Avogadros number</u>