Explanation:
According to Charle's law, at constant pressure the volume of an ideal gas is directly proportional to the temperature.
That is, 
Hence, it is given that
is 3.50 liters,
is 20 degree celsius, and
is 100 degree celsius.
Therefore, calculate
as follows.


= 17.5 liter
Thus, we can conclude that volume of gas required at 100 degree celsius is 17.5 liter.
The answer to this question is D! The ball and stick model! Hope this helps :)
Answer:
d. Heat is released from the reaction
Explanation:
A negative enthalpy change indicates that it is an exothermic reaction. Exothermic reactions release heat.
Answer: (3) 15
Explanation: We criss-cross down the oxidation numbers to get the subscripts for the correct formulas. That means the X has an oxidation number of 5. The element with the + oxidation number is always written first so it is +5. Of the groups names, only group 15 has +5 as an oxidation number.
Fluorine 20 (F - Atomic number 9 and atomic mass 20). Firstly we need to know what is beta decay. Beta decay occurs when one neutron changes into a proton and an electron therefore the atomic mass will remain the same as even though we loose a neutron it is replaced by a proton, the atomic number is always raised by 1 when one beta decay occurs. The produced electron is shot out of the nucleus at an incredible speed. This speedy electron we call a beta particle.
Ok now the reaction.
20 20 0
F -> Ne + e
9 10 -1
Remember the atomic number determines the nature of the element ( i.e what elemnt it is).
Hope this helps :).