Answer:
The percent by mass of water in this crystal is:
Explanation:
This exercise can be easily solved using a simple rule of three where the initial weight of the hydrated crystal (6,235 g) is taken into account as 100% of the mass, and the percentage to which the mass of 4.90 g corresponds (after getting warm). First, the values and unknown variable are established:
- 6,235 g = 100%
- 4.90 g = X
And the value of the variable X is found:
- X = (4.90 g * 100%) / 6,235 g
- X = approximately 78.6%.
The calculated value is not yet the percentage of the water, since the water after heating the glass has evaporated, therefore, the remaining percentage must be taken, which can be calculated by subtraction:
- Water percentage = Total percentage - Percentage after heating.
- <u>Water percentage = 100% - 78.6% = 21.4%</u>
It wouldn’t be a good idea bc metal absorbs the weather around it. so in florida it would be too hot and in alaska it would be too cold!
<h2>
Answer:</h2>
7 hydrogen atoms
<h2>
Explanation:</h2>
N<em><u>H4</u></em>C2<em><u>H3</u></em>02
In this problem we see the hydrogen atom twice, along with the numbers 4 and 3 next to them. (as shown above in bold & underlined)
So, in order to find how many there are in all you add both hydrogen atoms together-
H4+H3= H7
therefore, there are 7 hydrogen atoms in all
