Answer:
The heat of reaction when hydrogen and oxygen combine to form water is :
<u>C. 571.6 kJ</u>
Explanation:
Enthalpy Change = The enthalpy change for the formation of 1 mole of the substance from their standard state is called the enthalpy of formation.
This is intensive quantity as it is fixed for 1 mole .
Intensive properties = Those properties which are independent on the amount of the substance are intensive properties.
The value of these quantities does not get halve if you divide the substance into two equal parts. example , density, refractive index.
However , the enthalpy of reaction is extensive. Because on increasing the amount the value of the enthalpy also get doubles
Hence for this reaction :
Its value is -285.8 kJ for 1 mole
And here two moles are present . so the value of molar enthalpy is:
-285.8 x 2 = -571.6 kJ
Because metals that are more reactive than carbon wont react with it.
MThe heat energy required to raise the temperature of 0.36Kg of copper from 22 c to 60 c is calculate using the following formula
MC delta T
m(mass)= 0.360kg in grams = 0.360 x1000 = 360 g
c(specific heat energy) = 0.0920 cal/g.c
delta T = 60- 23 = 37 c
heat energy is therefore= 360g x0.0920 cal/g.c x 37 c= 1225.44 cal
Answer:
B = the number of protons
Explanation:
The atom of every elements differ from each other because of number of protons they have.
Every atom consist of neutron, proton and electron. Protons and neutrons are present with in nucleus while the electrons are present out side the nucleus.
All these three subatomic particles construct an atom. A neutral atom have equal number of proton and electron.
The number of neutrons may be same but every atom have different number of protons.
Neutron and proton are present inside the nucleus. Proton has positive charge while neutron is electrically neutral. Proton is discovered by Rutherford while neutron is discovered by James Chadwick in 1932.
Symbol of proton= P+
Symbol of neutron= n0
Mass of proton=1.672623×10-27 Kg
Mass of neutron=1.674929×10-27 Kg
Answer : The temperature of neon gas will be, 221.0 K
Explanation :
To calculate the temperature of neon gas we are using ideal gas equation.
where,
P = pressure of neon gas = 96.7 kPa = 0.955 atm
Conversion used : (1 atm = 101.3 kPa)
V = volume of neon gas = 9.50 L
T = temperature of neon gas = ?
R = gas constant = 0.0821 L.atm/mole.K
w = mass of neon gas = 10.00 g
M = molar mass of neon gas = 20 g/mole
Now put all the given values in the ideal gas equation, we get:
Therefore, the temperature of neon gas will be, 221.0 K
