Answer:
2(20+5)
2(10+15)
Step-by-step explanation:
When you add 20+5 together you get 25 which is the same to 2(25)
When you add 10+15 together you get 25 which is the same to 2(25)
167+57 written in base ten method
So, here you have to look at the periodic table and see what the molar mass of each molecule composing the water compound
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its two hydrogen atom plus an oxygen molecule, making it about 18g per mol.
That said, looking at the mass, we have to ask ourselves, if a mol of water contains 18g of mass, how many moles do we have in 0.5g of water?
We just do a cross multiplication:
It should be 11. hope this helps :)
60/500=36/x
60*x=500*36
x=(500*36)/60
x=(500*3)/5
x=300