D) 710 g
Step by Step:
Multiply 2.5 L by 2.0 M to solve for moles
2 mol/L • 2.5 L= 5 mol
Find formula weight of sodium sulfate
Na2SO4-142.04 g/mol
Na- 2(22.99)=45.98
S-32.06
O-4(16)=64
Multiply miles by formula weight
5 mole • 142.04 g/mol=710.2 g
It is equal to amount of thymine
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>:
Answer:
Baking soda = No. of atoms are 1 sodium + 1 Hydrogen + 1 carbon + 3 oxygens = 6 atoms per molecule.
Ions are atoms with a charge other than zero. In a neutral atom, the number of protons (positively charged particles) in the nucleus equals the number of electrons orbiting the nucleus.
Atoms can gain or lose electrons (not protons) resulting in a net charge other than zero. Atoms which lose electrons (usually metals) become positively charges, and atoms which gain electrons (usually nonmetals) become negatively charged.