Please help!!!!! i dont really know what the subject is so-

Nina [5.8K]

I think it might be 2 but I could be mistaken sorry if I am

7 0

3 years ago

The vapor pressure of liquid iodomethane, CH3I, is 40.0 mm Hg at 249 K.A sample of CH3I is placed in a closed, evacuated contain

lora16 [44]

Explanation:

It is given that vapor pressure of liquid iodomethane is 40.0 mm Hg. So, if we calculate the vapor pressure according to the given values and if its value will be greater than the the given vapor pressure of iodomethane then it means that some of the vapors has converted into liquid state.

As the given values are as follows.

$P_{1}$ = 72.0 mm Hg, $T_{1}$ = 404 K

$P_{2}$ = ? , $T_{2}$ = 249 K

As volume is constant so, according to Gay-Lussac's law pressure is directly proportional to temperature.

$P \propto T$ (at constant volume)

or, $\frac{P}{T}$ = k

Therefore, the formula to calculate the value of $P_{2}$ is as follows.

$\frac{P_{1}}{T_{1}}$ = $\frac{P_{2}}{T_{2}}$

$\frac{72.0 mm Hg}{404 K}$ = $\frac{P_{2}}{249 K}$

$P_{2}$ = 44.37 mm Hg

As calculated vapor pressure is more than the given vapor pressure. Hence, the liquid will convert into gas.

As a result, no condensation will occur and only vapors of iodomethane will be present.

5 0

3 years ago

It takes 26.8 mL of a 0.0700 M NaOH standard solution to neutralize a 250 mL sample of lactic acid (C3H6O3). What mass of lactic

Butoxors [25]

There is 1 OH- in 1 molecule of NaOH.
Also, there is 1 H+ in 1 molecule of lactic acid.

So the reaction is simple.
so just equate the moles
moles of OH- in NaOH = moles of H+ in lactic acid
26.8 x 0.07 = 250 x Mole of lactic
Moles of lactic = 0.0075

so mass = 0.0075 x 90.8 = 0.681 g

4 0

3 years ago

A chemist adds of a copper(II) sulfate solution to a reaction flask. Calculate the mass in kilograms of copper(II) sulfate the c

FrozenT [24]

Answer:

The question is incomplete as some details are missing. Here is the complete question ; A chemist adds 45.0mL of a 0.434M copper(II) sulfate CuSO4 solution to a reaction flask. Calculate the mass in grams of copper(II) sulfate the chemist has added to the flask. Round your answer to 2 significant digits

Explanation:

The step by step explanation is as shown in the attachment

8 0

3 years ago

How many grams are in 4.65 mol of AI(NO2)3

nirvana33 [79]

To find out how many grams are in 4.65 moles of Al(NO₂)₃
Find out what the molar mass of Al(NO₂)₃ is
Al = 26.98 g/mol Al
N = 14 g/mol N
O = 16 g/mol O
Next, you have to look at the subscripts and figure out which they belong to, in this case:
Al = 26.98 g/mol Al
N₃ = 42 g/mol N₃
O₆ = 96 g/mol O₆
Finally, add the numbers together, so:
26.98 g/mol Al + 42 g/mol N₃ + 96 g/mol O₆ =
164.98 g/mol Al(NO₂)₃
Now, you have 4.65 mol Al(NO₂)₃ so
164.98 g/mol Al(NO₂)₃ × 4.65 mol Al(NO₂)₃ =
767.157 grams of Al(NO₂)₃

6 0

3 years ago