Answer:
[α] = -77.5° / 
Explanation:
Given;
Mass of optically pure substance in the solution = 10 g
Volume of water = 500 mL
Length of the polarimeter, l = 20 cm = 20 × 0.1 dm = 2 dm
measured rotation = - 3.10°
Now,
The specific rotation ( [α] ) is given as:
[α] = 
here,
α is the measured rotation = -3.10°
c is the concentration
or
c = 
or
c = 
or
c = 0.02 g/mL
on substituting the values, we get
[α] = 
or
[α] = -77.5° / 
When the magnitude of the charge Q = I*T
when we have I current = 2.3
and T = 35 min * 60 = 2100 s
by substitution:
∴ Q = 2.3 * 2100
= 4830 C
according to this reaction equation:
Cu2+ + 2e- → Cu
we can see that 1 mol Cu2+ need 2 mol e- to produce Cu
mol of electron e- = Q / faraday's constant
= 4830 / 96485
= 0.05 mol
when 1 mol Cu2+ → 2 mol e-
?? ← 0.05 mol
∴ moles Cu2+ = 0.05 /2 = 0.025 mol
∴ mass Cu2+ = moles Cu2+ * molar mass Cu2+
= 0.025 * 64
= 1.6 g
Sodium’s combination with water creates a colourless result of sodium hydroxide (NaOH) and hydrogen gas (H2). ... The reaction is exothermic. During the reaction, the sodium metal become very hot, to the point where it can catch fire and burns with a characteristic orange colour.
Answer:
thermochemical equation
Explanation:
A(n)__thermochemical equation_____is a balanced chemical equation that includes the physical states of all reactants and products, and the energy change that accompanies the reaction.
Reactant + reactant = product
C + O2 = CO2
carbon dioxide is what's being made is product