Answer:
the molecular formula for the gas is NO₂
Explanation:
since it contains
Nitrogen = n → 30.45%
Oxygen = o → 69.55%
and 30.45%+69.55% = 100% , then the gas only contains nitrogen and oxygen
Also we know that the proportion of oxygen over nitrogen is
proportion of oxygen over nitrogen = moles of oxygen / moles of nitrogen
since
moles = mass / molecular weight
then for a sample of 100 gr of the unknown gas
mass of oxygen = 69.55%*100 gr = 69.55 gr
mass of Nitrogen = 30.45%*100 gr = 30.45 gr
proportion of oxygen over nitrogen = (mass of oxygen/ molecular weight)/(mass of nitrogen / molecular weight of nitrogen ) = (69.55 gr/ 16 gr/mol) /( 30.45 gr /14 gr/mol) = 1.998 mol of O/ mol of N≈ 2 mol of O/ mol of N
therefore there are 2 atoms of oxygen per atom of nitrogen
thus the molecular formula for the gas is:
NO₂
Answer:
c) Both the parts will weigh the same
Explanation:
center of gravity is based on weight so if you cut down the center of gravity you would have 2 equal parts
(might be D if it is cutting against the center of gravity)
Answer:
Explanation:
a ) Temperature at ground level is a field and it is scalar field .At any point in space near ground level , the temperature is specific so it is a field . It is scalar because temperature has no direction .
b )
Wind velocity at 100 feet above the ground is also a field but it is a vector field . At any point in space , the wind velocity is specific so it is a field . It is vector because velocity has a particular direction at any point .
c )
Gravitational force on Roessler Hall is a vector field because gravitational force also depends on location in space and it has direction.
d )
Height of a person in your group is not a space because it does not depend upon location is space . It is same for all location .
e )
Height (above sea level) of the ground is a field because it also depends upon location in space . It is scalar field .
f )
Slope of the surface of the earth is a scalar field .
Explanation:
The specific heat capacity is the heat or energy required to change one unit mass of a substance of a constant volume by 1 °C. The formula is Cv = Q / (ΔT ⨉ m) .
Answer:
Explanation:
Initially no of atoms of A = N₀(A)
Initially no of atoms of B = N₀(B)
5 X N₀(A) = N₀(B)
N = N₀ 
N is no of atoms after time t , λ is decay constant and t is time .
For A
N(A) = N(A)₀ 
For B
N(B) = N(B)₀ 
N(A) = N(B) , for t = 2 h
N(A)₀ = N(B)₀
N(A)₀ = 5 x N₀(A)
= 5
= 5 
half life = .693 / λ
For A
.77 = .693 / λ₁
λ₁ = .9 h⁻¹
= 5
Putting t = 2 h , λ₁ = .9 h⁻¹
= 5 
= 30.25
2 x λ₂ = 3.41
λ₂ = 1.7047
Half life of B = .693 / 1.7047
= .4065 hours .
= .41 hours .
