B. carbon-13 is not an allotrope of Carbon.
Allotropes<span> are elements on the periodic table that have more than one crystalline form. </span>Isotopes<span> are atoms of the same element with the same atomic number but have a different mass number.
C-13 is an isotope of carbon, not an allotrope.</span>
Among the choices, the unit of energy is calories. Answer in 1) is D. In 2) we are given with te mass , heat and temperature change. we just need to get the heat capacity and compare it with the following metals. The calculated heat capacity is 0.46 kJ/kg K. The answer is A. iron. In 3) we can compute the heat absorbed by the formula ΔH=mCpΔT. Cp of water is 4.18 J/g K. Answer of 3) is D. In 4) the formula used in Cp=ΔH/mΔT. Answer in 4) is A. The heat of enthalpy of fusion of ice is 80 cal/g. We convert this to J/g. Answer in 5) is B.334 J/g.
Hydrogen and oxygen are different elements.
when two or more elements combine, they form a compound
hence, two molecules of hydrogen and one molecule of oxygen combine to form water as a compound
1000 to the power 4 not so good at math but
Answer:
10.11 mL
Explanation:
Given that :
Total volume of decolorizer = 500 mL
A common recipe is equal parts 95% ethanol and acetone.
So;
The volume of 95% ethanol in the decolorizer = 500mL/2 = 250 mL
Let represent V(ml) for the 99% of ethanol needed to make 95% of the 250 mL of ethanol;
Therefore:
V(ml) × 0.99 = 250 × 0.95
V(ml) × 0.99 = 237.5
V(ml) = 237.5/0.99
V(ml) = 239.89 mL
Hence; the amount of water to be added to 95% of ethanol = ( 250 - 239.89 )mL = 10.11 mL