B. Most species that have lived on earth are now extinct. Ap3x
Carbon dioxide is a gaseous molecule made up of the elements, C and O. Each mole of carbon dioxide has one mole C and two mole oxygen atoms.
Molar mass of carbon dioxide (
)=
Percentage by mass of carbon = 
Percentage by mass of oxygen = 
Therefore C is 27.3 % and O is 72.7 % by mass in 1 mol CO
When calcium reacts with water, the temperature changes from 18c to 39c is an exothermic reaction as energy is releasing and increasing the temperature.
<h3>What is an exothermic reaction?</h3>
Exothermic reaction are those reactions in which energy is released when a reaction completes.
An example is burning of wood.
Thus, when calcium reacts with water, the temperature changes from 18c to 39c is an exothermic reaction as energy is releasing and increasing the temperature.
Learn more about exothermic reaction
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Answer:
The Nucleus...
it perform many activities and stores DNA in a cell.
The molarity of the hydrogen peroxide solution from the information supplied in the question is 12.26 M.
Co = 10pd/M
Where;
Co = concentration = ?
p = percent of the hydrogen peroxide = 30%
d = Density of hydrogen peroxide = 1.39 g/ml
M = Molar mass = 34 g/mol
Substituting values;
Co = 10 × 30 × 1.39/34
Co = 12.26 M
The molarity of the hydrogen peroxide solution from the information supplied in the question is 12.26 M.
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