I believe the correct answer would be option 4. The only statement that is true would be that it is difficult to responsibly dispose of nuclear waste products. This is because nuclear waste products are radioactive and are very harmful to the society and to the environment. It could cause serious damage to every being in contact to it.
Answer : The pressure in the flask after reaction complete is, 2.4 atm
Explanation :
To calculate the pressure in the flask after reaction is complete we are using ideal gas equation.

where,
P = final pressure in the flask = ?
R = gas constant = 0.0821 L.atm/mol.K
T = temperature = 
V = volume = 4.0 L
= moles of
= 0.20 mol
= moles of
= 0.20 mol
Now put all the given values in the above expression, we get:


Thus, the pressure in the flask after reaction complete is, 2.4 atm
A solid will start to melt when it reaches its melting point. For example the melting point of Helium is -272° Celsius and the melting point of Carbon is 3500° Celsius . Helium has the lowest melting point and carbon has the highest melting point in the periodic table.
26.7 moles of H2O
that is my answer to this
Answer: The molarity of each of the given solutions is:
(a) 1.38 M
(b) 0.94 M
(c) 1.182 M
Explanation:
Molarity is the number of moles of a substance present in liter of a solution.
And, moles is the mass of a substance divided by its molar mass.
(a) Moles of ethanol (molar mass = 46 g/mol) is as follows.

Now, molarity of ethanol solution is as follows.

(b) Moles of sucrose (molar mass = 342.3 g/mol) is as follows.

Now, molarity of sucrose solution is as follows.

(c) Moles of sodium chloride (molar mass = 58.44 g/mol) are as follows.

Now, molarity of sodium chloride solution is as follows.

Thus, we can conclude that the molarity of each of the given solutions is:
(a) 1.38 M
(b) 0.94 M
(c) 1.182 M