The intended sense is that of a reaction that depends on absorbing heat if it is to proceed. The opposite of an endothermic process is an exothermic process, one that releases "gives out" energy in the form of heat
Answer:
The partial pressure of Ar is 356.04 mm Hg (= 0.4685 atm)
Explanation:
<u>Step 1:</u> Data given
A mixture of three gases has a total pressure of 1380 mm Hg (=1.81579 atm) at 298 K
Moles of CO2 = 1.27 moles
Moles of CO = 3.04 moles
Moles of Ar = 1.50 moles
<u>Step 2:</u> Calculate total number of moles
Total number of moles = n(CO2)+ n(CO)+ n(Ar) = 1.27 mol+ 3.04 mol+ 1.50 mol = 5.81 moles
<u>Step 3:</u> Calculate mol fraction Ar
Mol fraction Ar = 1.50 mol/5.81 mol = 0.258
<u>Step 4</u>: Calculate partial pressure
1380 mm Hg * 0.258 moles Ar = 356.04 mm Hg = 0.4685 atm
The partial pressure of Ar is 356.04 mm Hg (= 0.4685 atm)
Correct answer is
<span>D. One atom accepts electrons from another.</span>
w/w percentage <span>
= mass of the pure compound /
total mass of the sample x 100%
70% HNO₃
contains by mass means every 100 g of sample has 70 g of HNO₃.</span><span>
The mass of solution = 103.8 g
Hence the mass of HNO₃ = 103.8 g x 70%</span><span>
= 103.8 g x (70 / 100)
<span>
= 72.66 g = 72.7 g.</span></span>
Depression is freezing point is a colligative property. It is mathematically expressed as ΔTf = Kf X m
where Kf = <span>freezing point depression constant = 1.86°c kg /mol (for water)
m = molality of solution = 1.40 m
</span>∴ ΔTf = Kf X m = 1.86 X 1.40 = 2.604 oC
Now, for water freezing point = 0 oC
∴Freezing point of solution = -2.604 oC
