Is salt and water after filtering a pure substance?

A 100g sample of a metal was heated to 100oC and then quickly transferred to an insulated container holding 100g of water at 22o

Lady_Fox [76]

Answer:

B) The metal temperature changed more than the water temperature did, but the metal lost

the same amount of thermal energy as the water gained.

Explanation:

Heat capacity or thermal capacity is defined as the amount of heat required by a given mass of a material to raise its temperature by one unit which means that the heat capacity of the water, that is the quantity of heat required to cause a rise from 22°C to 35°C that is a rise of 13°C is the quantity of heat that caused the drop in temperature of the metal from 100°C to 35°C a change of 65°C

The water has more capacity to absorb heat or a higher heat capacity than the metal

However, the first law of thermodynamics states that energy is neither created nor destroyed, but it changes from one form to another. In this case, the thermal energy lost by the metal is the same as the thermal or heat energy gained by the water

4 0

3 years ago

The concentration of HCl can be determined by titration with a primary standard such as Na2CO3 (sodium carbonate). The titration

Masteriza [31]

Answer:

The concentration of HCl is 0.275 M

Explanation:

Step 1: Data given

Mass of Na2CO3 = 0.521 grams

Molar mass of Na2CO3 = 105.99 g/mol

Volume of HCl = 35.7 mL

Step 2: The balanced equation:

2HCl + Na2CO3 → 2NaCl + CO2 + H2O

CO3(2-) + 2H+ ---> H2O + CO2

Step 3: Calculate moles of Na2CO3

Moles Na2CO3 = mass Na2CO3 / Molar mass Na2CO3

Moles Na2CO3 = 0.521 grams / 105.99 g/mol

Moles Na2CO3 = 0.0049 moles

Step 4: Calculate moles of HCl

For 1 mol of Na2CO3 consumed, we need 2 moles of HCl

moles of HCL = 2 * 0.0049 = 0.0098 moles HCl

Step 5: Calculate molarity of HCl

Molarity = number of moles of HCl / Volume (liters)

Molarity = 0.0098 moles / 0.0357 L

Molarity = 0.275 M

The concentration of HCl is 0.275 M

4 0

3 years ago

Read 2 more answers

A chemist dissolves 484 .mg of pure perchloric acid in enough water to make up 240.mL of solution. Calculate the pH of the solut

sdas [7]

Answer:

1.70

Explanation:

The molar mass of perchloric acid is 100.46 g/mol. The moles corresponding to 484 mg (0.484 g) are:

0.484 g × (1 mol/100.46 g) = 4.82 × 10⁻³ mol

4.82 × 10⁻³ moles are dissolved in 240 mL (0.240 L) of solution. The molar concentration of perchloric acid is:

4.82 × 10⁻³ mol/0.240 L = 0.0201 M

Perchloric acid is a strong monoprotic acid, that is, it dissociates completely, so [H⁺] = 0.0201 M.

The pH is:

pH = -log [H⁺] = -log 0.0201 = 1.70

8 0

3 years ago

17. If 5.00 L of an ideal gas is cooled from 24°C to - 27000

Elina [12.6K]

Answer:

V₂ = 448.44 L

Explanation:

Given data:

Initial volume = 5.00 L

Initial temperature = 24°C

Final volume = ?

Final temperature = -27000°C

Solution:

Final temperature = -27000 + 273 = 26727 K

Initial temperature = 24 +273 = 297 K

The given problem will be solve through the Charles Law.

According to this law, The volume of given amount of a gas is directly proportional to its temperature at constant number of moles and pressure.

Mathematical expression:

V₁/T₁ = V₂/T₂

V₁ = Initial volume

T₁ = Initial temperature

V₂ = Final volume

T₂ = Final temperature

Now we will put the values in formula.

V₁/T₁ = V₂/T₂

V₂ = V₁T₂/T₁

V₂ = 5.00 L × 26727 K / 297 k

V₂ = 133635 L.K / 298 K

V₂ = 448.44 L

8 0

3 years ago

Two reactions and their equilibrium constants are given. A + 2 B − ⇀ ↽ − 2 C K 1 = 2.79 2 C − ⇀ ↽ − D K 2 = 0.186 Calculate the

vfiekz [6]

Answer:

K=1.93

Explanation:

Given reactions are:

A +2B ⇄ 2C K1=2.79

2C ⇄ D K2=0.186

D⇄ A+ 2B K=?

If we reverse the reaction then the euillibrium constant also become reciprocal of original value:

3rd reaction is a combination of reciprocal of 1st and 2nd reaction

2C⇄A +2B 1/K1;........................1

D ⇄ 2C 1/K2; ..............................2

On adding 1 and 2

D ⇄A +2B $K=\frac{1}{K1} \times\frac{1}{K2};$

$K=\frac{1}{2.79} \times\frac{1}{0.186};$

K=1.93

4 0

3 years ago