To answer this question, we have to know the specific latent heat of vaporization of water, which is the amount of heat required to change one g/kg of water completely into vapor. Usually the question should provide with you with this info, but we can also look it up online, which should be 2256 kJ/kg.
Now we have to use the right formula. The only formula needed in this question is E = mlv. E is the total heat energy required, m is the mass of water, and lv is the specific latent heat of vaporization of water. We just have to substitute the numbers in to obtain the correct answer.
E = 0.0338 x 2256000
E = 76252.8 J
Therefore, the answer should be 76252.8 joules.
In chemistry he have to study atoms,molecules,etc.as u know these all are very small in their size.it is very hard to mesure the mass of a singal atom so scientist developed a new system that we call mole system.
<span>1 mole = 6.022 * 10^23.it is like 1 dozen = 12,1 grros =144 </span>
<span>2).11.1 MOLE of O2 is required. </span>
<span>3).69 g of O2 is used </span>
<span>4).239.14 g of CO2 & 146.73 g of H2O is made.</span>
power = work/time
watt = joule/sec
a) power = 0.10 watt = 0.1joules/sec
work = power * time
= 0.10 * 1 =0.1joules
work is northing but energy
therefore energy is 0.1joules
according to planks quantum theory E = nhν where nis the no. of photons ; h is planks constant; ν isfrequency
hence, n = E/hν
or n = Eλ/hc (ν = c/λ)
n = (0.1*700*10^-9)/6.625*10^-34*3*10^8 = 0.3522*10^18photons
b) similar to the above calculation
here E = 1.0joules
n = (1.0*700*10^-9)/6.625*10^-34*3*10^8 = 0.3522*10^17photons
Answer:
3.5 mL
Explanation:
Let us represent lauric acid with the symbol LaCOOH and the anion as LaCOO-. The reaction between the anion and H2SO4 is;
LaCOO-(aq) + H2SO4(aq) -----> LaCOOH(aq) + HSO4-(aq)
Number of moles of LaCOO- = 2.75 g/200 g/mol = 0.014 moles
Since the mole ratio of the reaction is 1:1, then the amount of H2SO4 required is also 0.014 moles
Then;
n = CV
n = number of moles
C= concentration
V = volume
V = n/C
V = 0.014 moles/4.0 M
V= 3.5 * 10^-3 L
V = 3.5 mL