How are the helium atoms in this model different from real helium atoms

How the metals react with oxygen? Give the general formula and explain the reaction of sodium with oxygen with chemical equation

slamgirl [31]

Answer:

Sodium is a very reactive metal, it tends to react with oxygen to form sodium oxide but this is an unstable compound and soon reacts with hydrogen to form sodium hydroxide. Sodium is the metal reacts vigorously with oxygen and water.

4 Na + O2 → 2 Na2O.

4 0

3 years ago

What are the concentrations of A , A, B , B, and C C at equilibrium if, at the beginning of the reaction, their concentrations a

Elenna [48]

The question is incomplete, here is the complete question:

A reaction

$A+B\rightleftharpoons C$

has a standard free-energy change of -4.88 kJ/mol at 25°C

What are the concentrations of A, B, and C at equilibrium if at the beginning of the reaction their concentrations are 0.30 M, 0.40 M and 0 M respectively?

Answer: The equilibrium concentrations of A, B and C are 0.117 M, 0.217 M, 0.183 M respectively.

Explanation:

Relation between standard Gibbs free energy and equilibrium constant follows:

$\Delta G^o=-RT\ln K_c$

where,

$\Delta G^o$ = Standard Gibbs free energy = -4.88 kJ/mol = -4880 J/mol (Conversion factor: 1 kJ = 1000 J)

R = Gas constant = $8.314J/K mol$

T = temperature = $25^oC=[273+25]K=298K$

$K_c$ = equilibrium constant of the reaction

Putting values in above equation, we get:

$-4880J/mol=-(8.3145J/Kmol)\times 298K\times \ln K_c\\\\K_c=7.17$

We are given:

Initial concentration of A = 0.30 M

Initial concentration of B = 0.40 M

Initial concentration of C = 0 M

The chemical reaction follows:

$A+B\rightleftharpoons C$

Initial: 0.30 0.40 0

At eqllm: 0.30-x 0.40-x x

The expression of equilibrium constant for the above reaction follows:

$K_c=\frac{[C]}{[A][B]}$

We are given:

$K_c=7.17$

Putting values in above equation, we get:

$7.17=\frac{x}{(0.30-x)\times (0.40-x)}\\\\x=0.183,0.657$

Neglecting the value of x = 0.657, because change cannot be greater than the initial concentration

So, equilibrium concentration of A = $(0.30-x)=(0.30-0.183)=0.117M$

Equilibrium concentration of B = $(0.40-x)=(0.40-0.183)=0.217M$

Equilibrium concentration of C = $x=0.183M$

Hence, the equilibrium concentrations of A, B and C are 0.117 M, 0.217 M, 0.183 M respectively.

5 0

3 years ago

Please help me with this question. I don’t understand how to do it

klasskru [66]

Use the Keq equation.. concentraion of products divided by concentration of reactants at equilibrium. (with coefficients as exponents, none in this case reaction is balanced)

Keq = [PCl5] / ([PCl3] [Cl2])

fill in given values and solve for [Cl2] using algebra. Im just going to sub in "c" for the unknown.

0.00094 = 0.44 / 0.33c
0.0003102c = 0.44
c = 1418.44 mol/L

5 0

3 years ago

Which electrons in an atom have the highest energy level

AleksandrR [38]

Valence electrons hope this helps

4 0

3 years ago

What limitations are associated with the use of both word and formula equations?

Dennis_Churaev [7]

Limitations of word equation and formula equation is that they do not express the quantities of reactant and product in the reaction.

Explanation:

Word equation expresses the chemical reaction in words. The reactants products and the direction of the reaction is mentioned in it. The information is used to write a chemical reaction. The word "reacted' shows the reactants and 'forms' show product. The sequence of reactions, moles of reactant and product is written.

Limitations:

Rate of reaction cannot be known.

Actual amount of product formed cannot be known.

eg: Addition of sodium oxide with water produces sodium hydroxide.

In formula equation symbols for element representation are used. The ratio of the elements in the reaction are also there. The atom numbers are indicated by the subscript number.

Limitations:

Concentration of both reactants and products is not mentioned.

The physical conditions of the reactants are not told

The thermodynamic conditions are not expressed as rate of reaction, pressure and temperature requirement.

Time taken to complete the reaction cannot be known.

Reaction mechanism cannot be observed by only chemical equations.

Value of actual yield is not given.

5 0

4 years ago