Chemistry High School

It's January in Nashville and your local weather station just informed you that the temperature outside is
15.4°F. You estimate the amount of ice on your driveway to be approximately 30 kg. What is the minimum amount
of sodium chloride in kilograms (kg) needed to lower the freezing point of the water so that the ice melts?

Answers

Answer 1

3.84 Kg of sodium chloride is needed to lower the freezing point of the water so that ice melts.

Explanation:

Data given:

mass of ice = 30 Kg

molar mass of NaCl = 58.5 grams/mole

ΔT(depression in freezing point) = 15.4 F  or - 9.22 degrees

Kf = 1.86 degree C/ mole

Molality = ?

mass of NaCl =?

i = 2 (because NaCl breaks into 2 ions)

ΔT = iKfm      equation 1

Depression in freezing point when ice melts, the temperature is 0 degrees so

the depression in temperature = 9.22 degrees

putting the values in the equation:

9.22 = 2 x 1.86 x [tex]\frac{mass}{58.5}[/tex] x[tex]\frac{1}{30}[/tex]

mass = 3.84 kg of NaCl will be required to lower the freezing point of the water so that the ice melts.

Related Questions

A prostate might be prescribed a total dose ionizing radiation of 72 Gy. In traditional units of rad, how many rad have been prescribed?

Answers

Answer:

7200RAD

Explanation:

Note

100RAD=1GY

Hence 72GY=7200RAD

Is it possible for a heat transfer system to involve both internal and external convection simultaneously?

Answers

Answer:

When the fluid is forced to flow over a surface it is external forced convection. When the fluid is forced to flow in a tube it is Internal forced convection. It is possible to have both Internal and external convection simultaneously as is case of pipe transporting a fluid in a windy area.

Explanation:

Li20 + MgCl2 → 2LiCl + Mgo

Name the second reactant:

Name the first product:

How many Lithiums on the product side?

Answers

Answer:

1. magnesium chloride

2. lithium chloride

3. 2

Explanation:

Know how to figure names (their are rules, be familiar with them)

Count the number

- Hope that helps! Let me know if you need further explanation.

Final answer:

In the reaction Li2O + MgCl2 → 2LiCl + MgO, the second reactant is magnesium chloride (MgCl2), the first product is lithium chloride (LiCl), and there are 2 lithium atoms on the product side.

Explanation:

The chemical reaction you are referring to is Li2O + MgCl2 → 2LiCl + MgO. In compliance with your question:

The second reactant in the equation is magnesium chloride (MgCl2).The first product of this reaction is lithium chloride (LiCl).On the product side, there are 2 lithium (Li) atoms, as indicated by the coefficient in front of LiCl.

It's essential to note that in a balanced chemical equation, the number of atoms of each element must be the same on both the reactants and the products side.

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