Answer:
Mg²⁵ = 10.00%
Mg²⁶ = 45.04%
Mg²⁴ = 44.96%
Explanation:
Given data:
Atomic mass of Mg²⁶ = 25.983
Atomic mass of Mg²⁵ = 24.986
Atomic mass of Mg²⁴ = 23.985
Abundance of Mg²⁵ = 10.00%
Abundance of Mg²⁶ = ?
Abundance of Mg²⁴ = ?
Solution:
Average atomic weight of Mg = 25.983 + 24.986+ 23.985 / 3
Average atomic weight of Mg = 74.954/3
Average atomic weight of Mg = 24.985 amu
Abundance of
Mg²⁵ = 10.00
Mg²⁶ = x
Mg²⁴ = 100- 10 - x = 90 -x
Formula:
Average atomic mass = (abundance of 1st isotope × its atomic mass) +(abundance of 2nd isotope × its atomic mass) + (abundance of 3rd isotope × its atomic mass) / 100
24.985 = (0.1×24.986)+(90-x×23.985) + ( x ×25.983 ) /100
24.985 = 249.86 + 2158.65 - 23.985x + 25.983x / 100
24.985 = 2408.51 + 1.998 x / 100
2498.5 = 2408.51 + 1.998 x
1.998 x = 2498.5 - 2408.51
1.998 x = 89.99
x = 89.99 /1.998
x = 45.04
Now we put the value of x:
Mg²⁵ = 10.00
Mg²⁶ = x (45.04)
Mg²⁴ = 90 -x (90 - 45.04 = 44.96)
Answer:
Thermal energy.
Explanation:
Anytime energy transfers between 2 places or things some of it is 'wasted' as thermal energy (heat). This could be by friction or a change in temperature from a reaction. We say it is wasted because this heat energy serves no purpose.
Multiply the mass by the abundance and add each. Make sure to convert the percentage into a decimal. (49.946 * .043) + (51.941 * .838) + (52.941 * .095) + (53.939 * .024) = 51.99 round up using sig figs and the answer is c. 52.00 amu
A serial dilution is the stepwise dilution of a substance in solution. Usually the dilution factor at each step is constant, resulting in a geometric progression of the concentration in a logarithmic fashion.
Answer:
Ni
Explanation:
An active metal is a highly reactive metal. Active metals are found high up in the activity series.
Active metals react with other metals that are lower than them in the activity thereby displacing the lower metals from a solution of their salts. This is what may have happened in the other two reactions.
Ni is the most active metal listed in the question since it can react a compounds with Pb(NO3)2(aq) to liberate Pb metal.
