Ask question

Ask question

All categories

3 years ago

8

Calculate the mole fraction of total ions in an aqueous solution prepared by dissolving 0.400 moles of mgcl2 in 850.0 g of water

.

1 answer:

lisov135 [29]3 years ago

5 0

0.0252 is the answer

You might be interested in

HELP ASAP!!! Why is cobalt (Co) placed before nickel (Ni) on

KatRina [158]

The answer is A or D

7 0

3 years ago

An element is identified as either a ..?

Alecsey [184]

Elements can be defined by their unique properties and atomic.

3 0

3 years ago

Ethanol (c2h5oh) melts at -114Â°c. the enthalpy of fusion is 5.02 kj/mol. the specific heats of solid and liquid ethanol are 0.9

Nimfa-mama [501]

Answer: 4.18925 kJ heat is needed to convert 25.0 g of solid ethanol at -135 °C to liquid ethanol at -50°C.

Explanation:

Temperature of Solid $C_2H_5OH=-135^oC=138 K(0^oC=273K)$

Melting temperature of Solid $C_2H_5OH=114^oC=159 K$

Temperature of liquid $C_2H_5OH=-50^oC=223K$

Specific heats of solid ethanol = 0.97 J/gK

Specific heats of liquid ethanol = 2.3 J/gK

Heat required to melt the the 25 g solid $C_2H_5OH$ at 159 K

$\Delta T_1$ = 159 K - 138 K = 21 K

$Q_1=mc\Delta T= 25\times 0.97J/gK\times 21 K=509.25 J$

Heat required to melt and raise the temperature of $C_2H_5OH$ upto 223 K

$\Delta T_2$ = 223 K - 159 K = 64 K

$Q_2=mc\Delta T= 25\times 2.3J/gK\times 64 K=3680 J$

Total heat to convert solid ethanol to liquid ethanol at given temperature :

$Q_1+Q_2=509.25 J+3680 J=4189.25 J=4.18925 kJ$ (1kJ=1000J)

Hence, 4.18925 kJ of heat will be required to convert 25.0 g of solid ethanol at -135 °C to liquid ethanol at -50°C.

6 0

3 years ago

A solid and a liquid are shaken together in a test tube to produce a clear blue liquid. Which of the following best describes th

harkovskaia [24]

<span>the behavior of the above pair of substances</span> is soluble

6 0

3 years ago

What is the mass percentage for copper ?

RideAnS [48]

Answer:

Explanation:

To find the mass percent composition of an element, divide the mass contribution of the element by the total molecular mass. This number must then be multiplied by 100% to be expressed as a percent.

3 0

2 years ago