Chlorofluoro carbons are air-polluting agents. They are produced by

Where do the sun rays hit Earth's surface nearly at right angles

hoa [83]

Answer:

The Sun Ray's hit earths surface at Earths Equator

8 0

2 years ago

Sodium metal reacts with water to produce hydrogen gas and sodium hydroxide according to the chemical equation shown below.

UNO [17]

Answer: The enthalpy change of the reaction is -361.6 kJ

Explanation:

To calculate the number of moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$

Moles of sodium = 0.025 moles

Molar mass of sodium = 23 g/mol

Putting values in above equation, we get:

$0.025mol=\frac{\text{Mass of sodium}}{23g/mol}\\\\\text{Mass of sodium}=(0.025mol\times 23g/mol)=0.575g$

We are given:

Mass of water = 100.00 g

Mass of sodium = 0.575 g

Mass of solution = 100.00 + 0.575 = 100.575 g

To calculate the amount of heat absorbed, we use the equation:

$q=m\times C\times \Delta T$

where,

q = amount of heat absorbed = ?

m = mass of solution = 100.575 g

C = specific heat capacity of solution = 4.18 J/g°C

$\Delta T$ = change in temperature = $(T_2-T_1)=(35.75-25.00)=10.75^oC$

Putting all the values in above equation, we get:

$q=100.575g\times 4.18J/g^oC\times 10.75^oC=4519.34J=4.52kJ$

When heat is absorbed by the solution, this means that heat is getting released by the reaction.

Sign convention of heat:

When heat is absorbed, the sign of heat is taken to be positive and when heat is released, the sign of heat is taken to be negative.

For the given chemical reaction:

$2Na(s)+2H_2O(l)\rightarrow NaOH(aq.)+H_2(g)$

When 0.025 moles of sodium is reacted, the heat released by the reaction is 4.52 kJ

So, when 2 moles of sodium will react, the heat released by the reaction will be = $\frac{4.52}{0.025}\times 2=361.6kJ$

Hence, the enthalpy change of the reaction is -361.6 kJ

6 0

3 years ago

Need some help :( !!

Ray Of Light [21]

Can you take picture of the whole question? I can’t see.

6 0

3 years ago

Convert 850 mm Hg to kPa. *

Feliz [49]

Answer:

113.324 KPA

Explanation:

4 0

3 years ago

Pleassse help!!!

11111nata11111 [884]

True

Explanation:

Harry Hess in 1961 resurrected Wegener's continental drift hypothesis and also he mantle convection idea of Arthur Holmes by postulating the theory of sea floor spreading.

After Wegener's postulation of the continental drift hypothesis, not much was done.
It was only around 1931 that Arthur Holmes came up with the idea of a convecting mantle.
After the second world war passed, new instruments were used to investigate and map the ocean floor.
Through this, Arthur Holmes came up with the idea of a spreading sea floor.
This gave a full gleam picture to the idea of a moving earth and the more accepted terminology of "Plate tectonics " came to the fore.

Learn more:

Sea floor spreading brainly.com/question/9912731

Continental drift brainly.com/question/5002949

#learnwithBrainly

8 0

3 years ago

Chlorofluoro carbons are air-polluting agents. They are produced by –