Density Grams or kilograms 
Volume is liters milliliters or cm cubed
        
             
        
        
        
Answer:
The mass of 2.35 moles of (NH4)3PO4 is 411.156 or 411.156 grams/g.
Explanation:
By calculating the mass of the formula, (NH4)3PO4, which equals up to 174.96 grams you divide 2.35 moles by 174.96 grams to equal 411.156 grams. The way to find out the mass is to multiple the molar mass of each chemical to the number beside it such as H multiplied by 4, P multiplied by 3, and so on. 
 
        
             
        
        
        
Explanation:
When we move across a period from left to right then there will occur an increase in electronegativity and also there will occur an increase in non-metallic character of the elements.
As calcium (Ca) is a group 2A element and rubidium (Rb) is a group 1A element. Hence, Rb being an alkali metal is more metallic in nature than calcium (alkaline earth metal).
Both magnesium (Mg) and radium (Ra) are group 2A elements. And, when we move down a group then as the size of element increases so, it becomes easy of the metal atom to lose an electron.
As a result, there occurs an increase in metallic character of the element. Hence, Radium (Ra) is more metallic in nature than magnesium (Mg).
Also, both bromine and iodine are group 17 elements. Since, both of them are non-metals and non-metallic character increases on moving down the group.
Therefore, bromine (Br) is more metallic than iodine.
 
        
             
        
        
        
Answer:
C: The atoms involved in the chemical reaction 
Explanation:
In a chemical reaction, when we balance it up, the number of moles or atoms on the left side must equal that on the right hand side. And thus, the mass is found in the atoms involved in such chemical reaction. 
 
        
             
        
        
        
<h3>
Answer:  Si   (choice D)</h3>
This is the element Silicon.
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Explanation:
First convert each percentage to its decimal form. 
For example, 92.2297% converts to 0.922297 after moving the decimal point two spots to the left.
After doing that, multiply those decimal values with their respective atomic mass unit (amu) values.
- 27.9769 * 0.922297 = 25.8030109393
- 28.9765 * 0.046832 = 1.357027448
- 29.9738 * 0.030872 = 0.9253511536
Then we add up the results
25.8030109393 + 1.357027448 + 0.9253511536 = 28.0853895409
That rounds to about 28.085
Then look at the periodic table to see the atomic mass of Cobalt (Co), Aluminum (Al), Nickel (Ni) and Silicon (Si). The mass values listed in the periodic table are weighted averages of all the isotopes. The units for the mass are still in amu.
- Cobalt = 58.933
- Aluminum = 26.982
- Nickel = 58.693
- Silicon = 28.085
We have a match with silicon, showing that <u>choice D</u> is the final answer.