Solve these problems like weighted averages:
The first one:
Multiply the masses (isotope numbers) by the decimal form of the percentage. Add them
0.076 (6) + 0.924 (7) = 6.924
The second one:
0.2 (10) + 0.8 (11) = 10.8
If you think about it, these answers make sense. 6.924 is much closer to 7 than to 6 (since there's a lot more lithium-7 than there is lithium-6). 10.8 is closer to 11 than to 10.
he total number of each of the atoms on the left and the right are the same thus the reaction equation is balanced.
<h3>What is the law of conservation of mass?</h3>
The law of conservation of mass states that, mass can neither be created nor destroyed. In view of the law of conservation of mass, the total mass of the reactants on the left-hand side must be the same as the total mass of products at the right hand side.
Thus is the total mass of the reactants and the products are not the same, it then follows that the reaction does not demonstrate the law of conservation of mass. In this case, the total number of each of the atoms on the left and the right are the same thus the reaction equation is balanced.
Learn more about conservation of mass:brainly.com/question/13383562
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Answer:skin cream
Explanation:
the independent variable is the variable that is always changed or manipulated. in this case the skin cream is the independent variable.
The formula we can use here is the Plancks equation:
E = h c / ʎ
where h is Plancks constant = 6.626 × 10-34 m2 kg / s, c
is speed of light = 3 x 10^8 m/s and ʎ is wavelength = 656.1 x 10^-9 m
Therefore E is:
E = (6.626 × 10-34 m2 kg / s)
* (3 x 10^8 m/s) / 656.1 x 10^-9 m
<span>E = 3.03 x 10^-19 J</span>
