Question

calculate the mass of 4moles of water​

Answer 1

Answer:

1 mole = 18 u

4 mole = 4×18 =72 amu or u ans

thanku

Answer 2

$\large{\underline{\underline{\mathfrak{\red{\sf{QUESTION:-}}}}}}$.

• calculate the mass of 4moles of water ?

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$\large{\underline{\underline{\mathfrak{\bf{SOLUTION:-}}}}}$.

In order to calculation this we need to equation

$\bold{\boxed{\boxed{\:mass(g)\:=\:moles\times\:Mr}}}$

where, Mr = Relative formula mass of a compound .

◼$\bold{\underline{\:Water\:has\:the\:formula\:H_{2}O}}$

This mean in every molecule of water there are two atom of hydrogen and one atom of oxygen .

In order to calculate , the Mr of water we need to find relative atomic mass (Ar) of hydrogen and oxygen .

Now

• Oxygen has an (Ar) = 16.

• Hydrogen has an (Ar) = 1.

So, (Mr) is equal to

$\bold{\boxed{\boxed{\:Mr\:=\:1\times\:(Ar)\:Of\:Oxygen\:+2\times\:(Ar)\:of\:Hydrogen}}}$

$\implies\:(Mr)\:=\:1\times\:16\:+\:2\times\:2$

$\implies\:(Mr)\:=\:16\:+\:2$

$\bold{\boxed{\boxed{\:(Mr)\:=\:18}}}$

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Now, using our original formula

$\bold{\boxed{\boxed{\:mass(g)\:=\:moles\times\:Mr}}}$

$\implies\:mass(g)\:=\:4\times\:18$

$\bold{\boxed{\boxed{\:mass(g)\:=\:72\:g}}}$

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$\large{\underline{\underline{\mathfrak{\green{\bf{ANSWER:-}}}}}}$.

• mass of 4 moles water = 72 g.

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