Which compound has the lowest melting point?<br> • CuO<br> • C6H12O6<br> K2Cr2O7<br> • BaCl2

Determine the freezing point and boiling point of a solution that has 68.4 g of sucrose

Ymorist [56]

Answer:

Freezing T° of solution = - 3.72°C

Boiling T° of solution = 101.02°C

Explanation:

To solve this we apply colligative properties. Firstly, freezing point depression:

ΔT = Kf . m . i

ΔT = Freezing T° of pure solvent - Freezing T° of solution

Kf = Cryoscopic constant, for water is 1.86 °C/m

m = molality (moles of solute in 1kg of solvent)

i = Ions dissolved in solution

Our solute is sucrose, an organic compound so no ions are defined. i = 1.

Let's determine the moles: 68.4 g . 1mol/ 342g = 0.2 moles

molality = 0.2 mol / 0.1kg of water = 2 m

We replace data: ΔT = 1.86°C/m . 2m . 1

Freezing T° of solution = - 3.72°C

Now, we apply elevation of boiling point: ΔT = Kb . m . i

ΔT = Boiling T° of solution - Boiling T° of pure solvent

Kf = Ebulloscopic constant, for water is 0.512 °C/m

We replace:

Boiling T° of solution - Boiling T° of pure solvent = 0.512 °C/m . 2 . 1

Boiling T° of solution = 0.512 °C/m . 2 . 1 + 100°C → 101.02°C

6 0

2 years ago

The boiling point of water is a _____ property and is equal to _____.

Reptile [31]

Answer:

The boiling point of water is a physical property and is equal to 0 C.

The Correct Answer is : C

3 0

3 years ago

Read 2 more answers

H2 + NO → H2O + N2<br><br><br> If 180.5 grams of N2 are produced, how many grams of H2 were reacted?

Lena [83]

Answer:

12.89 moles

Explanation:

Before we solve the question, we have to balance the equation of the reaction first. The balanced reaction will be:

2 NO + 2 H2→ N2 + 2 H2O

There are 180.5g of N2 produced, the number of produced in moles will be: 180.5g / (28g/mol)= 6.446 moles

The coefficient of H2 is two and the coefficient of N2 is one. Mean that we need two moles of H2 for every one mole of N2 produced. The number of H2 reacted will be: 2/1 * 6.446 moles = 12.89 moles

6 0

3 years ago

As you have seen, ozone is formed in the upper atmosphere through the reaction:

baherus [9]

The rate law equation for Ozone reaction

r=k[O][O₂]

<h3>Further explanation</h3>

Given

Reaction of Ozone :.

O(g) + O2(g) → O3(g)

Required

the rate law equation

Solution

The rate law is a chemical equation that shows the relationship between reaction rate and the concentration / pressure of the reactants

For reaction

aA + bB ⇒ C + D

The rate law can be formulated:

$\large{\boxed{\boxed{\bold{r~=~k.[A]^a[B]^b}}}$

where

r = reaction rate, M / s

k = constant, mol¹⁻⁽ᵃ⁺ᵇ⁾. L⁽ᵃ⁺ᵇ⁾⁻¹. S⁻¹

a = reaction order to A

b = reaction order to B

[A] = [B] = concentration of substances

So for Ozone reaction, the rate law (first orde for both O and O₂) :

$\tt \boxed{\bold{r=k[O][O_2]}}$

5 0

3 years ago

Your town is at sea level, and it is a comfortable room-

avanturin [10]

Answer:

68.6 m

Explanation:

Speed is defined as distance covered per unit time and expressed as

S=d/t

Where d is distance and t is speed.

Making d the subject of the above formula then

d=st

Substituting 343 m/s dor s and 0.200 s for s then

d=343*0.2=68.6 m

Therefore, the distance is 68.6 m

5 0

3 years ago

Which compound has the lowest melting point? • CuO • C6H12O6 K2Cr2O7 • BaCl2