Answer:
The chemist would require to use 43.43 grams.
Explanation:
In order to solve this problem we need to know<u> how much do 0.550 moles of selenium weigh</u>. To do that we use selenium's<em> molar mass </em>and multiply it by the given number of moles:
- 0.550 mol * 78.96 g/mol = 43.43 g
The chemist would require to use 43.43 grams.
Heat energy can be calculated by using the specific heat of a substance multiplying it to the mass of the sample and the change in temperature. It is expressed as:
Energy = mCΔT2520= 10.0(C) (70.0 - 10.0)C = 4.2 J/ kg K
<u>Answer:</u> The correct answer is option A.
<u>Explanation:</u>
To calculate the volume of an object, we use the formula:

We are given:
Density of an object = 
Mass of an object = 8.2 grams
Volume of an object = ?
Putting values in above equation, we get:


Hence, the correct answer is Option A.
A type of electromagnetic radiation would be electromagnetic waves
Sodium represents by the (Na).