<span> strictly speaking, a molecule has at least two atoms. ... Atoms with full valence electron shells are stable. Full Text[ edit ] The noble gases are a group of chemical elements that make up Group 18 on the periodic table.</span>
Explanation:
Given parameters:
Mass of sample = 235g
Molecular mass of sample = 128.1g
Empirical formula = CH₂O
Unknown:
Mass of each element in the sample = ?
Solution:
To solve this problem, we must know that the empirical formula of any compound is the simplest ratio of the atoms it contains. This is not the true formula of the compound.
Molecular formula = (Empirical formula)ₙ
Let us find the molecular mass of the sample;
CH₂O = 12 + 2(1) + 16 = 30g
128.1 = (30)n
n = 4
The molecular formula of the compound is; (CH₂O)₄ = C₄H₈O₄
Now to find the grams of each element in the sample;
Express the molecular mass of each element and that of the compound as a fraction and multiply with the given mass;
For C;
= 88.06g
H;
= 14.68g
O:
= 117.41g
learn more:
Mass composition brainly.com/question/3018544
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The correct answer is letter (d.) Mg, Ca, Sr, Ba
These four elements are found in Group 2 of the periodic table, which are alkaline metals, therefore they have the very similar properties because of their 2 valence electrons, which makes them reactive.