Answer : The mass of
needed are, 1.515 grams.
Explanation :
First we have to calculate the mole of
.

Now we have to calculate the moles of
.
The balanced chemical reaction will be,
produced from 1 mole of 
So, 0.005 mole of
produced from 0.005 mole of 
Now we have to calculate the mass of 


Therefore, the mass of
needed are, 1.515 grams.
scandium is a transition metal and shows a valency of 3.
The reaction between hydrogen and oxygen to form water is given as:

The balanced reaction is:

According to the balanced reaction,
4 g of hydrogen (
) reacts with 32 g of oxygen (
).
So, oxygen reacted with 29.4 g of hydrogen is:

Hence, the mass of oxygen that is reacted with 29.4 g of hydrogen is 235.2 g.
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...Diamond is the best conductor of heat, but heat also transmits readily through many other substances. Do you have multiple choice?