Answer:
E = 15×10⁻²⁹ J
Explanation:
Given data:
Frequency of photon = 2.2× 10⁷ Hz
Energy of photon = ?
Solution:
Formula:
E = h.f
h = 6.63×10⁻³⁴ Js
by putting values,
E = 6.63×10⁻³⁴ Js × 2.2× 10⁷ s⁻¹
E = 14.586 ×10⁻²⁹ J
E = 15×10⁻²⁹ J
The energy of photon is 15×10⁻²⁹ J.
It is typically formed by the evaporation of salty water (such as sea water) which contains dissolved Na+ and Cl- ions. One finds rock salt deposits ringing dry lake beds, inland marginal seas, and enclosed bays and estuaries in arid regions of the world
Concentration of Solutions is oftenly expressed in Molarity. Molarity is the number of moles of solute dissolved per volume of solution.
Molarity = Moles / Volume
As,
Moles = Mass / M.mass
So,
Molarity = Mass / M.mass × Volume ---- (1)
Data Given;
Volume = 0.750 L
Mass = 52 g
M.mass = 180 g/mol
Putting Values in eq.1,
Molarity = 52 g ÷ (180 g.mol⁻¹ × 0.750 L)
Molarity = 0.385 mol.L⁻¹
Answer:
the stoichiometric coefficient for cobalt is 3
Explanation:
the unbalanced reaction would be
Co(NO₃)₂+ Al → Al(NO₃)₃ + Co
One way to solve is to build a system of linear equations for each element (or group as NO₃) , knowing that the number of atoms of each element is conserved.
For smaller reactions a quick way to solve it can be:
- First the Co as product and as reactant needs to have the same stoichiometric coefficient
- Then the Al as product and as reactant needs to have the same stoichiometric coefficient
- After that we look at the nitrates . There are 2 as reactants and 3 as products . Since the common multiple is 6 then multiply the reactant by 3 and the product by 2.
Finally the balanced equation will be
3 Co(NO₃)₂+ 2 Al → 2 Al(NO₃)₃ + 3 Co
then the stoichiometric coefficient for cobalt is 3
