It could both the 2nd and the 3rd,
because if you add the exponents (2 + 1 + 6 = 9) you don't get 10.
and also each orbital level can and has to carry 2 electrons, and the 2s only has 1 there.
Answer: The concept behind hydroelectric power is simple: Rather than combusting fossil fuels, like coal, oil, or natural gas, which put over 52 million kilotons of greenhouse gases into the atmosphere each year, dams block the water flowing in rivers or lakes and use the force of the would-be flow to turn turbines,
Explanation:
Volume of NaOH required to react = 145.5 ml
<h3>Further explanation</h3>
Reaction
CO₂(g)
+ 2 NaOH(aq) ⇒Na₂CO₃(aq) + H₂O(l)
The volume of CO₂ : 0.45 L
mol CO₂ at STP (O C, 1 atm) ⇒ at STP 1 mol gas 22.4 L :
From the equation, the mol ratio of CO₂ : NaOH = 1 : 2, so mol NaOH :
Then volume of NaOH :
Answer:
2.2 °C/m
Explanation:
It seems the question is incomplete. However, this problem has been found in a web search, with values as follow:
" A certain substance X melts at a temperature of -9.9 °C. But if a 350 g sample of X is prepared with 31.8 g of urea (CH₄N₂O) dissolved in it, the sample is found to have a melting point of -13.2°C instead. Calculate the molal freezing point depression constant of X. Round your answer to 2 significant digits. "
So we use the formula for <em>freezing point depression</em>:
In this case, ΔTf = 13.2 - 9.9 = 3.3°C
m is the molality (moles solute/kg solvent)
- 350 g X ⇒ 350/1000 = 0.35 kg X
- 31.8 g Urea ÷ 60 g/mol = 0.53 mol Urea
Molality = 0.53 / 0.35 = 1.51 m
So now we have all the required data to <u>solve for Kf</u>:
