Chemical property of the substance but then again it could be physical
Answer:
The total work is 4957.45J
Explanation:
For an ideal gas, at constant temperature the definition of work (W) is

where P is the pressure, V the volume, n the moles number, T the temperature and R the gas constant.
To solve the problem is necessary to replace the two steps in the equation
Stape 1: n = 1 mol, R = 0.082atm.L/K.mol, T = 77ºC = 350K, Pi = 5.50atm and Pf = 2.43atm.

Stape 2: n = 1 mol, R = 0.082atm.L/K.mol, T = 77ºC = 350K, Pi = 2.43atm and Pf = 1.00atm.

The total work is the sum of the two steps

The choices for this question can be found elsewhere and as follows:
<span>A. A single polypeptide may have quaternary structure.
B. Hydrogen bonds may hold the polypeptides in contact.
C. A quaternary protein cannot have fewer than two carboxyl groups.
I think the correct answer from the choices is option A. The statement a </span>single polypeptide may have quaternary structure is not true.
Answer:
5.88atm
Explanation:
First, we obtain the number of mole of CO2 present in the vessel. This is illustrated below:
Molar Mass of CO2 = 12 + (2x16) = 12 + 32 = 44g/mol
Mass of CO2 from the question = 345.1g
Number of mole of CO2 =?
Number of mole = Mass/Molar Mass
Number of mole of CO2 = 345.1/44
= 7.84moles
Now we can easily calculate the pressure by doing the following:
Data obtained from the question include:
V (volume) = 32.1 L
T (temperature) = 20°C = 20 + 273 = 293K
R (gas constant) = 0.0821atm*L/mole*K
n (number of mole) = 7.84moles
P (pressure) =?
We will be making use of the ideal gas equation PV = nRT to calculate the pressure
PV = nRT
P = nRT/V
P = 7.84 x 0.0821 x 293/32.1
P = 5.88atm
Therefore, the pressure is 5.88atm
Answer:
- The limiting reactant is lead(II) nitrate.
- 7.20 g of precipitate are formed.
- 1.9 g of the excess reactant remain.
Explanation:
The reaction that takes place is:
- Pb(NO₃)₂(aq) + 2KCl(aq) → PbCl₂(s) + 2KNO₃(aq)
With a percent yield of 87.5%.
To determine the limiting reactant, first we <u>convert the masses of each reactant to moles</u>, using their molar mass:
- 9.82 g Pb(NO₃)₂ ÷ 331.2 g/mol = 0.0296 mol Pb(NO₃)₂
- 5.76 g KCl ÷ 74.55 g/mol = 0.0773 mol KCl
Looking at the stoichiometric coefficients, we see that 1 mol of Pb(NO₃)₂ would react completely with 2 moles of KCl. Following that logic, 0.0296 mol Pb(NO₃)₂ would react completely with (2x0.0296) 0.0592 mol of KCl. We have more than that amount of KCl, this means KCl is the reactant in excess and Pb(NO₃)₂ is the limiting reactant.
To calculate the mass of precipitate (PbCl₂) formed, we <u>use the moles of the limiting reactant</u>:
- 0.0296 mol Pb(NO₃)₂
*
* 87.5/100 = 7.20 g PbCl₂
- Keeping in mind the reaction yield, the moles of Pb(NO₃)₂ that would react are:
- 0.0296 mol Pb(NO₃)₂ * 87.5/100 = 0.0259 mol Pb(NO₃)₂
Now we <u>convert that amount to moles of KCl and finally into grams of KCl</u>:
- 0.0259 mol Pb(NO₃)₂
*
= 3.86 g KCl
3.86 g of KCl would react, so the amount remaining would be: