Consider the following equation:0.0136 g + 2.70 × 10-4 g - 4.21 × 10-3 g = ? How many digits to the right of the decimal point should be used to report the result? =2, Choose the correct answer=9.66 × 10^-3 g, Which metric unit would be the best choice to report the result?=mg
That would be phosphorus. It’s electron configuration is 1s^2 2s^2 2p^6 3s^2 3p^3
Answer:
Option A (0.043 g) is the correct answer.
Explanation:
Given:
= 43 mg
As we know,

then,
⇒ 
Thus, the above is the correct alternative.
When oxygen is found is peroxide, it has an oxidation number of -1.
The chemical formula of hydrogen peroxide is H2O2. We know that hydrogen always has +1 oxidation state until it forms metal hydrides. So in H2O2, the oxidation state ofhydrogen is +1.
Now, let oxidation state of oxygen be x. So,
2 * (+1) + 2*x = 0
2 + 2x = 0
2x = -2
x = -2 / 2
x = -1
Hence, the oxidation number of oxygen in peroxides is -1