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3 years ago

How are physical and chemical changes similar?

2 answers:

8 0

Physical changes occur when substances undergo a change that does not change their chemical composition. It doesnot includes change in chemical composition.
Chemical change is the change that causes the formation of new chemical substance.
A.Neither can change the number of atoms of each element that are present, is the correct answer.

mr Goodwill [35]3 years ago

7 0

I believe the correct response is the first option.

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Which of the following energy does NOT travel as a wave?

frosja888 [35]

Answer:

Wind

Explanation:

It's impossible for them to travel in a wave.

3 0

3 years ago

Could someone help me with this?

Varvara68 [4.7K]

Solving part-1 only

KMnO_4

Transition metal is Manganese (Mn)

Actually it's the oxidation number of Mn

Let's find how?

$\\ \tt\Rrightarrow x+1+4(-2)=0$

$\\ \tt\Rrightarrow x+1-8=0$

$\\ \tt\Rrightarrow x-7=0$

$\\ \tt\Rrightarrow x=+7$

x is the oxidation number

Purple as per the color of potassium permanganate

$\boxed{\begin{array}{c|c|c}\boxed{\bf Tube} &\boxed{\bf Charge} &\boxed{\bf No\:of\; electrons\: loss}\\ \sf 2 &\sf +6 &\sf 6e^-\\ \sf 3& \sf +2 &\sf 2e- \\ \sf 4 &\sf 4 &\sf 4e^-\end{array}}$

7 0

2 years ago

For the reaction 2 H2S(g) D 2 H2 (g) + S2 (g), Kp = 1.5 × 10−5 at 800.0°C. If the initial partial pressures of H2 and S2 in a cl

Usimov [2.4K]

Answer: The approximate equilibrium partial pressure of $H_2S$ is 3.92 atm

Explanation:

Equilibrium constant is the ratio of the concentration of products to the concentration of reactants each term raised to its stochiometric coefficients.

The given balanced equilibrium reaction is,

$2H_2S(g)\rightleftharpoons 2H_2(g)+S_2(g)$

$K_p=\frac{[H_2]^2\times [S_2]}{[H_2S]^2}$

$1.5\times 10^{-5}=\frac{[H_2]^2\times [S_2]}{[H_2S]^2}$

On reversing the reaction:

$2H_2(g)+S_2(g)\rightleftharpoons 2H_2S(g)$

initial pressure 4.00atm 2.00 atm 0

eqm (4.00-2x)atm (2.00-x) atm 2x atm

$K_p=\frac{[H_2S]^2}{[H_2]^2\times [S_2]}$

$K_p'=\frac{1}{K_p}=0.67\times 10^5$

$2H_2(g)+S_2(g)\rightleftharpoons 2H_2S(g)$

$0.67\times 10^5=\frac{2x]^2}{[4.00-2x]^2\times [2.00-x]}$

$x=1.96$

$[H_2S]=2x=2\times 1.96=3.92 atm$

Thus approximate equilibrium partial pressure of $H_2S$ is 3.92 atm

3 0

3 years ago

Using the van der waals equation, the pressure in a 22.4 L vessel containing 1.50 mol of chlorine gas at 0.00 c is____________at

MatroZZZ [7]

Answer:

D. 1.48atm

Explanation:

Van der waals equation is given as:

(P +an²/v²) (v - nb) = nRT

Where;

P = pressure (atm)

V = volume (L)

R = gas constant (0.0821 Latm/molK)

a and b = gas constant specific to each gas

T = temperature (K)

n = number of moles

According to the given information; V = 22.4L, T = 0.00°C (273.15K), R = 0.0821 Latm/molK, a = 6.49L^2-atm/mol^2, b = 0.0562 L/mol, n = 1.5mol

Hence;

(P + 6.49 × 1.5²/22.4²) (22.4 - 1.5×0.0562) = 1.5 × 0.0821 × 273.15

(P + 6.49 × 2.25/501.76) (22.4 - 0.0843) = 33.638

(P + 0.0291) (22.316) = 33.638

22.316P + 0.649 = 33.638

22.316P = 33.638 - 0.649

22.316P = 32.989

P = 32.989/22.316

P = 1.478

P = 1.48atm

6 0

3 years ago

Can someone help me lol;) WILL MARK BRAINLIEST

inn [45]

Answer:

See explanation

Explanation:

1 ) Al has physical and chemical properties, similar to Boron, because It's also part of group 13, also called the boron group. The elements are characterized by having three valence electrons.

2) Lithium is in group 1. This means it has 1 valence electron.

Nitrogen has 7 electrons. The first shell can only have 2 electrons, so the second and outer shell has 5 electrons. Those 5 electrons are the 5 valence electrons;

Neon is a noble gas, it's in the stable noble gas configuration. This means it has 8 valence electrons.

Oxygen = non-metal because it's a gas

Silicon = metalloid

Helium = non-metal because it's a gas

Arsenic = metalloid

Sodium = it's an (alkali) metal, It is physically silver colored and is a soft metal of low density. Pure sodium is not found naturally on earth because it is a highly reactive metal

Chlorine = non-metal

Tin = Is a soft, ductile and highly crystalline silvery-white metal

Boron = it does conduct electricity. Its chemical properties are mostly, but not entirely, and non-metallic

lead = is a heavy metal that is denser than most common materials

Radon = metalloid

Cesium = It is a soft, silvery-golden alkali metal

Carbon = non metal

Period

⇒ Horizontal from left to right

⇒ same number of atomic orbitals

⇒period = row

Group

⇒ vertical colums

⇒same number of valence electrons

⇒ same physical and chemical properties

4 0

3 years ago