The solution to the polynomial expression since the power of the variable is in the second degree is 6.29 × 10² cm
<h3>What is the power of a variable?</h3>
The power of a variable refers to the exponent of the variable and the highest power of a variable is the degree to which the variable is being raised. From the information given, the highest power of the variable is a polynomial.
Given that:

So, since the exponents are in the same power we are going to add them all together multiplied by their exponent.
i.e.


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We know that
, where
is density,
is mass, and
is volume.
Substitute in the values we know and solve:

Answer:
Mass = 20,000 g
Explanation:
Given data:
Mass of MgO formed = ?
Mass of Mg react = 12 Kg (12 Kg × 1000/1 Kg = 12000 g)
Solution:
Chemical equation:
2Mg + O₂ → 2MgO
Number of moles of Mg:
Number of moles = mass/molar mass
Number of moles = 12000 g/ 24 g/mol
Number of moles = 500 mol
Now we will compare the moles of Mg and MgO.
Mg : MgO
2 : 2
500 : 500
Mass of MgO:
Mass = number of moles × molar mass
Mass = 500 mol × 40 g/mol
Mass = 20,000 g