2) A container has an unknown quantity of gas at a pressure of 61.6 kPa, a volume of 3.9 liters, and a temperature

Please help.<br><br> Why does the temperature change when a powder is dissolved in water?

Schach [20]

Answer:

In order for the powder to dissolve, each powder molecule must separate from the other powder molecules and be surrounded by water molecules. This shift in arrangement either absorbs or releases energy depending on the situation. It is due to the exchange of energy that the temperature of the solution fluctuates.

Explanation:

:)

5 0

3 years ago

Give the name and formula of the compound formed from the following elements: (a) sodium and nitrogen; (b) oxygen and strontium;

lisov135 [29]

<u>Answer:</u>

<u>For a:</u> The chemical name and chemical formula formed is sodium nitride and $Na_3N$

<u>For b:</u> The chemical name and chemical formula formed is strontium oxide and $SrO$

<u>For c:</u> The chemical name and chemical formula formed is aluminium chloride and $AlCl_3$

<u>Explanation:</u>

For formation of a neutral ionic compound, the charges on cation and anion must be balanced. The cation is formed by loss of electrons by metals and anions are formed by gain of electrons by non metals.

The nomenclature of ionic compounds is given by:

1. Positive is written first.

2. The negative ion is written next and a suffix is added at the end of the negative ion. The suffix written is '-ide'.

<u>For a:</u> Sodium and nitrogen:

Sodium is the 11th element of periodic table having electronic configuration of $[Ne]3s^1$

To form $Na^{+}$ ion, this element will loose 1 electron.

Nitrogen is the 7th element of periodic table having electronic configuration of $[He]2s^22p^3$ .

To form $N^{3-}$ ion, this element will gain 3 electrons.

By criss-cross method, the oxidation state of the ions gets exchanged and they form the subscripts of the other ions. This results in the formation of a neutral compound.

So, the chemical formula for sodium nitride is $Na_3N$

<u>For b:</u> Oxygen and strontium

Strontium is the 38th element of periodic table having electronic configuration of $[Kr]5s^2$ .

To form $Sr^{2+}$ ion, this element will loose 2 electrons.

Oxygen is the 8th element of periodic table having electronic configuration of $[He]2s^22p^4$ .

To form $O^{2-}$ ion, this element will gain 2 electrons.

By criss-cross method, the oxidation state of the ions gets exchanged and they form the subscripts of the other ions. This results in the formation of a neutral compound.

So, the chemical formula for strontium oxide is $SrO$

<u>For c:</u> Aluminium and chlorine

Aluminium is the 13th element of periodic table having electronic configuration of $[Ne]3s^23p^1$

To form $Al^{3+}$ ion, this element will loose 3 electrons.

Chlorine is the 17th element of the periodic table having electronic configuration of $[Ne]3s^23p^5$

To form $Cl^{-}$ ion, this element will gain 1 electron.

By criss-cross method, the oxidation state of the ions gets exchanged and they form the subscripts of the other ions. This results in the formation of a neutral compound.

So, the chemical formula for aluminium chloride is $AlCl_3$

4 0

4 years ago

A standard solution contained 0.8 mg/mL. A student took 2 mL of the standard solution and added 10 mL of water. What is the new/

galben [10]

To get the concentration of the second solution let us use the following formulae

C1V1=C2V2 where C1 is concentration of first solution and V1 is the volume of solution first solution. on the other hand C2 is the concentration of second solution and V2 is the volume of second solution.

therefore

0.8×2=(2+10)×C2
1.6 =12×C2
1.6/12=C2
C2 = 0.1333mg/mL

7 0

3 years ago

Read 2 more answers

A filament for a light bulb needs to conduct electricity. Which of the elements listed below might be useful as a light bulb fil

horrorfan [7]

Answer:

A. tungsten

Explanation:

Tungsten is a material which high melting point ie. does not melt easily incase of high temperature

8 0

3 years ago

Read 2 more answers

Convert 90.23 kPa into atm

svlad2 [7]

Answer:

The answer is

Explanation:

To convert from kPa to atm we use the conversion

101.325 kPa = 1 atm

If

101.325 kPa = 1 atm

Then

90.23 kPa will be

$\frac{90.23}{101.325} \\ =0.89050086...$

We have the final answer as

Hope this helps you

6 0

3 years ago