<h3>
<u>moles of H2SO4</u></h3>
Avogadro's number (6.022 × 1023) is defined as the number of atoms, molecules, or "units of anything" that are in a mole of that thing. So to find the number of moles in 3.4 x 1023 molecules of H2SO4, divide by 6.022 × 1023 molecules/mole and you get 0.5646 moles but there are only 2 sig figs in the given so we need to round to 2 sig figs. There are 0.56 moles in 3.4 x 1023 molecules of H2SO4
Note the way this works is to make sure the units are going to give us moles. To check, we do division of the units just like we were dividing two fractions:
(molecules of H2SO4) = (molecules of H2SO4)/1 and so we have 3.4 x 1023/6.022 × 1023 [(molecules of H2SO4)/1]/[(molecules of H2SO4)/(moles of H2SO4)]. Now, invert the denominator and multiply:
<h3 />
A physical change.
Physical change = can be reverted + doesn't change substance
Chemical = changes substance
Answer:
a.) It is a chemical reaction because a new substance was formed and a colour change occurred in the reaction.
b.) Iron- Metallic element
sulpher- Non-Metalic element
Iron Sulphide- Compound
HOPE IT HELPS....
The weighted average of the nail in accordance with the given data is 11.176g.
<h3>How to calculate weighted average?</h3>
Weighted average is an arithmetic mean of values biased according to agreed weightings.
The weighted average of the nail in the image above can be calculated by multiplying the decimal abundance with the mass of the nail, then summed up as follows;
Weighted average = (decimal abundance × mass 1) + (decimal abundance × mass 2)
Weighted average = (0.12 × 3.3) + (0.88 × 12.25)
Weighted average = 0.396 + 10.78
Weighted average = 11.176g
Therefore, 11.176g is the weighted average of the nail
Learn more about weighted average at: brainly.com/question/28042295
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