The colour imparted to a flame by calcium ion?

A lab scientist cools a liquid sample of water (2.6 kg) at 0.00°C to -192°C. The water turns to ice as this temperature change o

soldier1979 [14.2K]

Answer: The heat released for the given process is -1892 kJ

Explanation:

The processes involved in the given problem are:

$1.)H_2O(l)(0^oC,273K)\rightarrow H_2O(s)(0^oC,273K)\\2.)H_2O(s)(0^oC,273K)\rightarrow H_2O(s)(-192^oC,81K)$

Pressure is taken as constant.

To calculate the amount of heat released at same temperature, we use the equation:

$q=m\times L_{f,v}$ ......(1)

where,

q = amount of heat released = ?

m = mass of water/ice

$L_{f,v}$ = latent heat of fusion or vaporization

To calculate the amount of heat released at different temperature, we use the equation:

$q=m\times C_{p,m}\times (T_{2}-T_{1})$ .......(1)

where,

q = amount of heat released = ?

$C_{p,m}$ = specific heat capacity of medium

m = mass of water/ice

$T_2$ = final temperature

$T_1$ = initial temperature

Calculating the heat absorbed for each process:

For process 1:

Converting the latent heat of fusion in J/kg, we use the conversion factor:

1 kJ = 1000 J

So, $(\frac{-334kJ}{1kg})\times (\frac{1000J}{1kJ})=-334\times 10^3J/kg$

We are given:

$m=2.6kg\\L_f=-334\times 10^3J/kg$

Putting values in equation 1, we get:

$q_1=2.6kg\times (-334\times 10^3J/kg)=-868400J$

For process 2:

We are given:

$m=2.6kg\\C_{p,s}=2050J/kg.K\\T_1=273K\T_2=81K$

Putting values in equation 2, we get:

$q_2=2.6kg\times 2050J/kg.K\times (81-(273))^oC\\\\q_2=1023360J$

Total heat absorbed = $q_1+q_2$

Total heat absorbed = $[-868400+(-1023360)]J=-1891760J=-1891.76kJ\approx -1892kJ$

Hence, the heat released for the given process is -1892 kJ

3 0

3 years ago

Can someone help please? :)

Leno4ka [110]

1) This is a definition.

2) Protons are given by the bottom number (since atomic number = number of protons).

3) Neutrons = (mass number)-(atomic number), which are the top and bottom numbers, respectively.

4) Nuclear fusion involves combining two things together, which is only reflected by the last option.

5) This is a fact.

6) This is a fact.

7) This is a fact.

8) This is a fact.

9) The correct option is the explanation.

7 0

2 years ago

The slant of the earth is called what

suter [353]

I think the slant would be called the tilt

8 0

3 years ago

Read 2 more answers

Which type of reaction is the Haber process: N2(g) + 3 H2(g) → 2 NH3(g) + heat? *

Alik [6]

Answer:

exothermic, with a decrease in entropy

Explanation:

Whenever you produce heat as a product in a reaction, the reaction is exothermic. To determine entropy, we know we have 4 moles of gas on reactant (1 from N2 and 3 from H2) and in produce side we only have two moles (2 from NH3) thus since we are decreasing the number of gas molecules, there is going to be less disorder, hence decrease in entropy.

8 0

3 years ago

. In the absence of the sodium-potassium pump, the extracellular solution becomes hypotonic relative to the inside of the cell.

andriy [413]

Answer:

sdfsdfsfsdf

Explanation:

sdfsfdsfsf

8 0

3 years ago