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>:
7. Atomic mass
8. Atomic number
9. Chemical symbol
10. Right
Answer: An oxygen atom in heavy water has an extra neutron. A hydrogen atom in heavy water has an extra proton.
Explanation:
Answer:
Xenon is less reactive.
Explanation:
Xenon is a noble gas with 8 valence electrons whereas bromine is a halogen with 7 and is very reactive.
In the complete combustion of 1.60 moles of benzene, C6H6, 12 moles of oxygen, O2, is consumed.
Combustion is defined as the process of burning something. In chemistry, combustion refers to the chemical process between a fuel and an oxidant, usually oxygen to produce heat and light in the form of flame.
In a complete combustion, oxygen is sufficient to react with any hydrocarbons to produce carbon dioxide and water.
Balancing the combustion reaction of benzene, we have:
2C6H6 + 15 O2 = 12CO2 + 6H2O
Based on the balanced combustion reaction above, 2 moles of benzene requires 15 moles of oxygen to have a complete combustion.
If we have 1.60 moles C6H6,
moles O2 = mole ratio x mole of benzene
moles O2 = (15 moles O2/2 moles C6H6) x 1.60 moles C6H6
moles O2 = 12
To learn more about combustion: brainly.com/question/9913173
#SPJ4
