The piece of unknown metal is in thermal equilibrium with water such that Q of metal is equal to Q of the water. We write this equality as follows:
-Qm = Qw
Mass of metal (Cm)(ΔT) = Mass of water (Cw) (ΔT)
where C is the specific heat capacities of the materials.
We calculate as follows:
-(Mass of metal (Cm)(ΔT)) = Mass of water (Cw) (ΔT)
-68.6 (Cm)(52.1 - 100) = 42 (4.184) (52.1 - 20)
Cm = 1.717 -----> OPTION C
Answer:
λ=2167.6 nm
The wavelength of light emitted is 2167.6 nm.
Explanation:
We recall that Eₙ=
since there was transition from n7 to n=4 we will first calculate the change in the energy i.e ΔE
ΔE=E₄-E₇
ΔE=
ΔE=-9.1760*10^-20 J
Now:
|ΔE|=Energy of photon=h*v=h*c/λ
λ=h*c/|ΔE|
λ=
λ=2.1676*10^-6 m
λ=2167.6*10^-9 m
λ=2167.6 nm
The wavelength of light emitted is 2167.6 nm.
Reaction won't occur
Because the activity of Cu is less than Al
Answer:
This approximation of mass can be used to easily calculate how many neutrons an element has by simply subtracting the number of protons from the mass number. Protons and neutrons both weigh about one atomic mass unit or amu. Isotopes of the same element will have the same atomic number but different mass numbers.
Explanation:
