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olya-2409 [2.1K]
3 years ago
12

;_; help please i need help TwT

Chemistry
2 answers:
Airida [17]3 years ago
6 0

Answer:

it's a day I think so ........

Tems11 [23]3 years ago
3 0

Answer:

Lunar cycle

Explanation:

Year is the amount of time for the Earth to rotate a complete circle around the sun.

Lunar cycle (moon phases) is the rotation of the Moon around the Earth.

Day is the time for the Earth to rotate on its own axis completely.

Solar cycle is the changes that the sun's electric field goes through about every 11 years.

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DNA contains genes that provide instructions for inherited traits. What is the relationship between the genes and chromosomes?
lara31 [8.8K]

Answer:

Genes are segments of DNA that are located on the chromosomes of each cell.

Explanation:

Chromosomes are basically tightly bundled thingies containing genes, DNA, whatever. Phenotype and genotype have nothing to do with chromosomes, that's just how WE describe them.

5 0
3 years ago
How many valence electrons are in Lead(IV)
Ksenya-84 [330]

Answer:

It has 4 valence electrons

7 0
3 years ago
A gas balloon has a volume of 80.0 mL at 300K, and a pressure of 50.0 kPa. If the pressure changes to 80 kPa and the temperature
fomenos

Answer:  The new volume is 53.3 ml

Explanation:

The combined gas equation is,

\frac{P_1V_1}{T_1}=\frac{P_2V_2}{T_2}

where,

P_1 = initial pressure of gas =  50.0 kPa

P_2 = final pressure of gas = 80.0 kPa

V_1 = initial volume of gas = 80.0 ml

V_2 = final volume of gas = ?

T_1 = initial temperature of gas = 300K

T_2 = final temperature of gas = 320K

Now put all the given values in the above equation, we get:

\frac{50.0\times 80.0}{300}=\frac{80.0\times V_2}{320}

V_2=53.3ml

The new volume is 53.3 ml

4 0
3 years ago
Tris has a molecular weight of 121 g/mol. How many grams of Tris would you need to make 100 mL of a 100 mM solution of Tris
Zepler [3.9K]

Answer:

1.21 g of Tris

Explanation:

Our solution if made of a solute named Tris

Molecular weight of Tris is 121 g/mol

[Tris] = 100 mM

This is the concentration of solution:

(100 mmoles of Tris in 1 mL of solution) . 1000

Notice that mM = M . 1000  We convert from mM to M

100 mM . 1 M / 1000 mM = 0.1 M

M = molarity (moles of solute in 1 L of solution, or mmoles of solute in 1 mL of solution). Let's determine the mmoles of Tris

0.1 M = mmoles of Tris / 100 mL

mmoles of Tris = 100 mL . 0.1 M → 10 mmoles

We convert mmoles to moles → 10 mmol . 1mol / 1000mmoles = 0.010 mol

And now we determine the mass of solute, by molecular weight

0.010 mol . 121 g /mol = 1.21 g

8 0
3 years ago
Identify solute and solvent in 80 solution of ethyl alcohol with water
diamong [38]
The solute is the part of the solution that dissolves in the second component (usually a fluid). Therefore, for the mentioned solution, the solute is ehyl alcohol since it is the one dissolving in water.

As for the solvent, it is the component in which the solute dissolves. In this case, it is water.
5 0
3 years ago
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