Answer:
I cannot give you all the answer but I can help you to solve those.
Explanation:
The first question:
How many grams are there in 7.5×
molecules of 
?
So we need to find the molecular mass first, use your periodic table,
And then we can find out 2+32+16×4=98 g/mol
Then, we need to find how many moles, by using Avogadro's constant:
Avogadro's constant: 1 mole = 6.02×
∴
=1.25 mol(2d.p.)
Lastly, find the grams using the formula 
m=Mn
m=1.25*98
m=122.5g
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In conclusion, use those formula to help you:
(which M = molecular mass(atomic mass) m=mass of the substance and n = moles)
Avogadro's constant: 
Answer:
V
Explanation:
Firstly let’s list the names of the atoms
1. Sodium
2. Magnesium
3. Aluminum
4. Oxygen
5.Chlorine
Generally, anions have greater electron affinity than cations. Hence, they have more positive values for this electron affinity. This means that the higher the electron affinity, the greater its positive value
Electron affinity increases across a period. Thus, it is expected that chlorine has the highest value
Answer:
m= 6.9905 = 7 g
Explanation:
The formula is m= M.n
m= mass (g), M= Molar mass (g/mole), n= moles (moles)
Molar mass of Cu is 63.55
=) m= 63.55*0.11
m= 6.9905 = 7 g
Answer:
Extensive is the answer of this question?
