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saveliy_v [14]
3 years ago
8

When 14.8 g KOH is dissolved in 85.6 g of water in a coffee-cup calorimeter, the temperature rises from 19.3 °C to 32.76 °C. Wha

t is the enthalpy change per gram of potassium hydroxide dissolved in the water?
Chemistry
1 answer:
KonstantinChe [14]3 years ago
6 0

Answer:

This question is incomplete, the complete question is; assuming that the solution has a specific heat of 4.18 J/g°C

The answer is 381.67 J/g

Explanation:

Enthalpy change denoted by ΔH can be calculated using the formula;

ΔH = m × c × ΔT

Where; m= mass of reactants

c= specific heat

ΔT = change in temperature

ΔT = T2 - T1

ΔT = 32.76 - 19.3

ΔT = 13.46 °C

mass of reactants= 85.6 + 14.8 = 100.4g, c = 4.18J/g°C

Hence; ΔH = m × c × ΔT

ΔH = 100.4 × 4.18 × 13.46

ΔH = 5648.78J

Enthalpy change per gram of potassium hydroxide dissolved in the water is;

ΔH = 5648.78/14.8

ΔH = 381.67 J/g

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MArishka [77]

Answer:

0.033 M

Explanation:

Let's consider the neutralization reaction between NaOH and HCl.

NaOH + HCl → NaCl + H₂O

0.4 L of 0.1 M NaOH were used. The reacting moles of NaOH are:

0.4 L × 0.1 mol/L = 0.04 mol

The molar ratio of NaOH to HCl is 1:1. The reacting moles of HCl are 0.04 moles.

0.04 moles of HCl are in 1.2 L. The molarity of HCl is:

M = 0.04 mol / 1.2 L = 0.033 M

4 0
3 years ago
In preparation for a demonstration, your professor brings a 1.50−L bottle of sulfur dioxide into the lecture hall before class t
solmaris [256]

Answer:

4.81 moles

Explanation:

The total pressure of the gas = Pressure at which gauge reads zero + pressure read by it.

Pressure at which gauge reads zero = 14.7 psi

Pressure read by the gauge = 988 psi

Total pressure = 14.7 + 988 psi = 1002.7 psi

Also, P (psi) = P (atm) / 14.696

Pressure = 1002.7 / 14.696  = 68.2297 atm

Temperature = 25 °C

The conversion of T( °C) to T(K) is shown below:

T(K) = T( °C) + 273.15  

So,  

T = (25 + 273.15) K = 298.15 K  

Volume = 1.50 L

Using ideal gas equation as:

PV=nRT

where,  

P is the pressure

V is the volume

n is the number of moles

T is the temperature  

R is Gas constant having value = 0.0821 L.atm/K.mol

Applying the equation as:

68.2297 atm × 1.5 L = n × 0.0821 L.atm/K.mol × 298.15 K  

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3 years ago
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nikitadnepr [17]

The answer is 42 grams of NaF are there in 1 mole.

<h3>What is a mole ?</h3>

A mole is defined as 6.022 × 10²³ atoms, molecules, ions, or other chemical units.

and the molar mass of a substance is defined as the mass of 1 mole of that substance, expressed in grams per mole.

It is equal to the mass of 6.022 × 10²³ atoms, molecules, or formula units of that substance.

Molar Mass , i.e. mass of 1 mole of NaF is sum of molar mass of Na and F

23 + 19

42 grams

Therefore 42 grams of NaF Sodium-fluoride are there in 1 mole.

To know more about mole

brainly.com/question/26416088

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