The density of the block will be "7.11 gm/cm³". A further explanation is provided below.
Given values are:
Density of iron,
Mass of block of metal,
Volume of block,
By using the formula,
→ 
then,
→ The density of block will be:
= 
= 
= 
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1. Rapid combustion - <span>used in engines and rockets souring. Large amount of energy produced.
</span>2. R<span>espiration - </span><span>a type of slow combustion. Organic matter is transfered into energy and carbon dioxide.
3. Soaring - a chemical change. A</span>cidification of milk into soured milk.<span>
4. Oxidation - electron loss when combining with another element. Metals gave electrons to nonmetals and became cations.
5. C</span>alcium - element in bone which absorbs X-rays. Calcium increases the photoelectric effect<span> which increase absorption of X-rays.
6. P</span>hotosynthesis reaction in which the product is glucose. Plants produce glucose from carbon dioxide and water.
<span>they exercise regularly, which improves the efficiency of their heart.
Hope this helps!
-Payshence xoxo</span>
In exactly 1 mol Hg₂(NO₃)₂ , there are 2 mol Hg, 2 mol N and 6 mol O.
Since the molecular formula of Hg₂(NO₃)₂ shows that for every mole of the substance, we have 2 moles of Hg, 2 moles of N and 6 moles of O.
So, in exactly 1 mol Hg₂(NO₃)₂ , there are 2 mol Hg, 2 mol N and 6 mol O.
Learn more about number of moles here:
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4 is correct for this one
