This problem is asking for the percent by mass of hydrogen in hydrofluoric acid. At the end, the answer turns out to be D. 5% as shown below:
<h3>Percent compositions:</h3>
In chemistry, percent compositions are used for us to know the relative amount of a specific element in a compound. In order to do so for hydrogen, we use the following formula, which can also be applied to any other element in a given compound:

Where
stands for the atomic mass of hydrogen and
for the molar mass of hydrofluoric acid. In such a way, we plug in the atomic masses of hydrogen (1.01 g/mol) and fluorine (19.0 g/mol) to obtain:

Learn more about percent compositions: brainly.com/question/12247957
True because it doesn’t count as a full number
The correct answer is option 1. Carbon dioxide is nonpolar because the shape of the molecule is symmetrical. It is a linear molecule where the oxygen atoms are symmetrical on each end. CO2 molecule do not have a region of unequal sharing.
Answer:
a) To determine the facilities that contribute the most to recycling check the pie chart and select the facility with the largest portion while to determine the facilities that contribute the least to recycling check the pie chart and select the facility with the smallest portion
b) Energy is saved because the products which are recycled usually require less energy to turn them into usable materials
c) It saves energy through recycling. It helps sustains the environment. It decrease the emission of green house gases
Explanation:
The question is not complete
a) Pie chart is the graphical representation of information in which the information is represented in a circle. The circle is divided into segments and the portion with the largest segment has the highest percentage.
To determine the facilities that contribute the most to recycling check the pie chart and select the facility with the largest portion while to determine the facilities that contribute the least to recycling check the pie chart and select the facility with the smallest portion
b) Extraction and processing of raw resources to make end products requires a lot of energy. With recycling energy is saved because the products which are recycled usually require less energy to turn them into usable materials
c) It saves energy through recycling. It helps sustains the environment. It decrease the emission of green house gases.
Copper wire is not an example of a pure element because although it's made by pure elements, it's not one itself. It's made by factories.
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