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Naddik [55]
2 years ago
14

15 points will mark brainliest

Chemistry
2 answers:
dybincka [34]2 years ago
6 0

Answer:

Option b as 100 years before also rain was not there is sahara dessert and now also it is not there..

Vladimir [108]2 years ago
4 0
You got it right, the answer is d
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What determines how ionic bonds will form?
Harrizon [31]

Answer:

I think the answer should be B. Number of valence electrons

8 0
3 years ago
A gas is allowed to expand from a volume of 400 ml to 2000 ml at a constant temperature. If the the initial pressure is 3 atm, c
Lostsunrise [7]

Answer:

P_{2}) = 0.6 \; atm

Explanation:

<u>Given the following data;</u>

Initial volume = 400 mL

Final volume = 2000 mL

Initial pressure = 3 atm

To find the final pressure P2, we would use Boyles' law.

Boyles states that when the temperature of an ideal gas is kept constant, the pressure of the gas is inversely proportional to the volume occupied by the gas.

Mathematically, Boyles law is given by;

PV = K

P_{1}V_{1} = P_{2}V_{2}

Substituting into the equation, we have;

3 * 400 = P_{2}* 2000

1200 = 2000P_{2}

P_{2}) = \frac {1200}{2000}

P_{2}) = 0.6 \; atm

8 0
3 years ago
A sample of 9.00 grams of aluminum metal is added to an excess of hydrochloric acid. The volume of hydrogen gas produced at stan
marysya [2.9K]

Answer:

The volumen of hydrogen (H) is 11.22 L

Explanation:

The balanced reaction between the aluminum (Al) and the hydrochloric acid (HCl) is:

2Al(s) + 6HCl(l) --> 2AlCl3(ac) + 3H2(g)

It is a reduction-oxidation reaction.

At the beginning we have 9.00 grams of Al what represents an certain amount of moles. Then, we know the molar mass of Al is 26.9815 g/mol, so the moles content in 9.00 g of Al are :

9.00 g Al * (1 mol Al / 26.9815 g Al)= 0.33356 mol Al

Now, we have to conisdered the molar relation between the Al and H2, according to the balanced reaction performed above. That is 2:3 (Al:H2)

Then,

0.33356 mol Al * (3 mol H2/  2mol Al) = 0.50034 mol H2

In this point, we can considered the H2 like a noble gas, because the question ask for standard temperature and pressure (0° C= 273.15K and 1 atm).

Let us remember the noble gases equation

PV=nRT

P: pressure

V: Volumen

n: number of moles

R: gases constant

T: temperature

For the volumen, the equation is:

V= (nRT/P)

Now: V= (0.50034 mol * 0.0821 (L*atm/K*mol) * 273.15 K)/ (1 atm)

         V= 11.22 L

3 0
3 years ago
HELPPPPPP PLZZZz i'll mark brainliest! Infrared (IR) and ultraviolet (UV) light. But above 29°C, the coating on the glass underg
Elena L [17]

Answer:

It goes away

Explanation:

cause the IR light only can see through clean glass.

8 0
2 years ago
Read 2 more answers
Explain how the periodic table can help in writing electron configurations
Hoochie [10]
Period : the no. of electron shells
group: the last no. of electron configuration
4 0
3 years ago
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