Answer:
When light is shone on to the surface of a metal, its electrons absorb small amounts of energy and become excited into one of its many empty orbitals. The electrons immediately fall back down to lower energy levels and emit light. This process is responsible for the high luster of metals.
Explanation:
<em> </em><em>Your </em><em>well-wisher</em><em> </em><em>:-)</em>
Answer:
C. Al
Explanation:
2Al+ 3H2SO4(l)------> Al2(SO4)3+ 3H2
Answer:
1gram of water
Explanation:
First balance the equation
Ch4+2O2>CO2+2H2O
Ratio is 1:2
500×10-3what about 2?
500×10-3×2=1g
1g of water
Answer:
T = 215.33 °C
Explanation:
The activation energy is given by the Arrhenius equation:

<u>Where:</u>
k: is the rate constant
A: is the frequency factor
Ea: is the activation energy
R: is the gas constant = 8.314 J/(K*mol)
T: is the temperature
We have for the uncatalyzed reaction:
Ea₁ = 70 kJ/mol
And for the catalyzed reaction:
Ea₂ = 42 kJ/mol
T₂ = 20 °C = 293 K
The frequency factor A is constant and the initial concentrations are the same.
Since the rate of the uncatalyzed reaction (k₁) is equal to the rate of the catalyzed reaction (k₂), we have:

(1)
By solving equation (1) for T₁ we have:
Therefore, we need to heat the solution at 215.33 °C so that the rate of the uncatalyzed reaction is equal to the rate of the catalyzed reaction.
I hope it helps you!
Answer:
The correct answer is b polar covalent
Explanation:
When two atoms joined by covalent bond has difference in their electronegativities at that time polarity arise.
When the electronegativity difference is low such as 1.3 then the polar bond formed by the two atoms are called polar covalent bond.For example H2O
on the other hand polar bond formed by two atoms having high difference in their electronegativities is called ionic bond.For example NaCl.