Answer:
Here's what I get.
Explanation:
Mg + 2HCl ⟶ MgCl₂ + H₂
According to the Law of Conservation of Mass, the total mass of the products must equal the total mass of the reactants.
However, one of the products is a gas, hydrogen. The gas escapes into the atmosphere, so you will not be weighing it at the end of the reaction.
The mass of the test tube and contents after the reaction will be less than before the reaction.
However, that doesn't violate the Law of Conservation of Mass. You just didn't measure the mass of all the products.
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
hi these are the answers :)
One kilogram is equal to one thousand grams. Further, one gram is equal to 1000 mg. The conversion is as shown below,
(6.285 x 10³ mg) x (1 g / 1000 mg) x (1 kg / 1000 g)
The numerical value of the operation above is 0.006285 kg.
