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3 years ago

Why should the oil be removed from a low pressure system at 130F

1 answer:

6 0

When removing oil from a low pressure system, the temperature should be 130°F because, less refrigerant will be contained in the oil at higher temperature. Liquid charge into a deep vacuum will boil and may lower temperatures enough to freeze water in the tubes.

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The densities of gases a, b, and c at stp are 1.25 g/l, 2.86 g/l and 0.714 g/l, respectively. calculate the molar mass of each s

kicyunya [14]

The molar mass of a, b and c at STP is calculated as below

At STP T is always= 273 Kelvin and ,P= 1.0 atm

by use of ideal gas equation that is PV =nRT
n(number of moles) = mass/molar mass therefore replace n in the ideal gas equation

that is Pv = (mass/molar mass)RT
multiply both side by molar mass and then divide by Pv to make molar mass the subject of the formula

that is molar mass = (mass x RT)/ PV

density is always = mass/volume

therefore by replacing mass/volume in the equation by density the equation
molar mass=( density xRT)/P where R = 0.082 L.atm/mol.K

the molar mass for a
= (1.25 g/l x0.082 L.atm/mol.k x273k)/1.0atm = 28g/mol

the molar mass of b
=(2.86g/l x0.082L.atm/mol.k x273 k) /1.0 atm = 64 g/mol

the molar mass of c

=0.714g/l x0.082 L.atm/mol.K x273 K) 1.0atm= 16 g/mol

therefore the
gas a is nitrogen N2 since 14 x2= 28 g/mol
gas b =SO2 since 32 +(16x2)= 64g/mol
gas c = methaneCH4 since 12+(1x4) = 16 g/mol

8 0

3 years ago

When an atom undergoes beta decay, wich of the following is true?

tigry1 [53]

<span> The atomic number increases by one and the element becomes a different element. </span>

3 0

4 years ago

In a reaction, 25 grams of reactant

Vsevolod [243]

Answer:

D. 15g

Explanation:

The law of conservation of mass states that, in a chemical reaction, mass can neither be created nor destroyed. This means that the amount of matter in the elements of the reactants must be equal to the amount in the resulting products.

In this question, 25 grams of a reactant AB, was broken down in a reaction to produce 10 grams of products A and X grams of product B. According to the law of conservation of mass, the mass of the reactant must be equal to the total mass of the products. This means that 25 grams must also be the total mass of both products in this reaction. Hence, if product A is 10 grams, product B will be 25 grams - 10 grams = 15 grams.

Therefore, product B must be 15 grams in order to form a total of 25 grams when added to the mass of product A. This will equate the mass of the reactant AB and fulfill the law of conservation of mass.

8 0

3 years ago

Is weathering long term or short term and why

Marrrta [24]

Long term because if you leave something out to be weathered then it can’t be unweathered because of the drastic change of the object.

4 0

3 years ago

For each chemical equation below, write the number of product molecules that will form from the reaction.

Gekata [30.6K]

Answer:

a. 5 moles of CO₂

b. 2 moles of NaCl

c. 3 moles of H₂CO₃

Explanation:

1a. Carbon reacts with oxygen to produce carbon dioxide according to equation below:

C + O₂ ----> CO₂

From the equation of reaction, one mole of carbon reacts with one mole of oxygen to produce one mole of carbon dioxide.

In the given reaction, therefore, 5 moles of carbon will only react with 5 moles of oxygen to produce 5 moles of carbon dioxide. Oxygen is in excess, carbon is the limiting reactant and 5 moles of carbon dioxide are produced. The equation is given below :

5 C + 6 O₂ ---> 5 CO₂

1b. Sodium reacts with chlorine to produce sodium chloride according to the equation below:

2 Na + Cl₂ ---> NaCl

From the equation of reaction, 2 moles of sodium reacts with one mole of chlorine to produce one mole of sodium chloride.

In the given reaction, therefore, 4 moles of sodium will react with only 2 moles of chlorine to produce 2 moles of sodium chloride. Chlorine is in excess, sodium is the limiting reactant and 2 moles of sodium chloride are produced. The equation is given as follows: 4 Na + 8 Cl₂ ---> 2 NaCl

1c. Carbon dioxide reacts with water to produce carbonic acid according to the equation: CO₂ + H₂O ---> H₂CO₃

From the equation of reaction one mole of carbon dioxide reacts with one mole of water to produce one mole of carbonic acid.

In the given reaction, therefore, 3 moles of carbon dioxide will react with only 3 moles of water to produce 3 moles of carbonic acid. Water is in excess, carbon dioxide is the limiting reactant and 3 moles of carbonic acid are produced. The equation is given as follows: 3 CO₂ + 4 H₂O ---> 3 H₂CO₃

4 0

3 years ago