Answer:
1540.8 Joules of energy is required to bring a 30 gram crayon from room temperature, 25 degrees C, to its melting point 49 degrees C
Explanation:
Crayon is paraffin wax. The specific heat of paraffin wax is 2.14 J/g°C
As we know

Where
is the change in temperature 
m is the mass of the object
c is the specific heat in J/g°C
Substituting the given values, we get -
Joules
1540.8 Joules of energy is required to bring a 30 gram crayon from room temperature, 25 degrees C, to its melting point 49 degrees C
Answer:
C. Sb has a lower ionization energy and a lower electronegativity than I.
Explanation:
The chemical elements present higher ionization energy the higher and to the right of the periodic table they are.
Electronegativity usually increases from left to right over a period of the periodic table and from top to bottom in the groups.
Answer:
3)The rate of the forward reaction is equal to the rate of the reverse reaction
B.gas would has the most kinetic enegry because its particles move freely
The pH of pure water is neutral because the concentration of hydronium ions equals that of hydroxide ions.
Answer: Option A
<u>Explanation:</u>
Water is one of the most important constituents of living being. It is said that there is no life without water. So that water need to neutral in nature to save life. Pure water is composed of hydronium
and hydroxide
ions. It is known that hydronium ions are acidic in nature with concentration of
.
Similarly, the hydroxide ions which are basic in nature will be in same concentration as that of hydronium ions. So, as the concentration of basic and acidic elements are equal with the same strength of pH, the combination of these ions lead to formation of pure water with the pH being neutral.