-In Africa savanna more wildebeest are born than the environment can support. As a result over a period of years individuals that are well suited to the environment reproduce, and those that have lesser adaptations die before they reproduce. This is referred to as natural selection.
The answer is C
I just took the test
Number of Moles are calculate by using following formula,
Moles = Mass / M.mass --- (1)
M.mass is calculated by adding the atomic masses of all elements present in molecule, Since, MgCl₂ contains one Mg (atomic mass = 24.3 g/mol) and two Cl atoms (atomic mass = 35.45 × 2 = 70.9 g/mol), So,
Molar mass = 24.3 g/mol + 70.9 g/mol
Molar Mass of MgCl₂ = 95.2 g/mol
Now, putting values in eq. 1,
Moles = 310 g ÷ 95.2 g/mol
Moles = 3.256 moles
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