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1 year ago

How is the life cycle of a star similar to that of a human?

Chemistry

2 answers:

VLD [36.1K]1 year ago

7 0

Answer:

The most common similarity is that they live and die

Explanation:

Arturiano [62]1 year ago

6 0

Answer: They both have stages where they are born and die which is in the main sequence and supernova and in a human they are born in a womb and die of old age.

Explanation:

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Is Boyle's law universally true? if not mention one of the its limitations

murzikaleks [220]

Yes because look in the book dh

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2 years ago

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34kurt

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2 years ago

I really need an answer by tonight!

Anton [14]

The water cycle iss a process which helps to circulate and replenish water on earth.

<h3>What is hydrology?</h3>

Hydrology is the scientific study of water bodies , the changes that occur in them as well as the various features and behavior of water bodies such as oceans and rivers.

Water circulation created by prevailing wind systems. The Gulf Stream is an example up of the Coriolis effect.

The length of open sea over which wind can blow steadily to create waves is called fetch.

Salinity is the amount of dissolved salt in a liquid

The distance from the crest of one wave to the crest of another is called wavelength

Water circulation created by differences in density deepwater currents

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Learn more about water cycle at: brainly.com/question/2164391

5 0

1 year ago

An aqueous KNO3 solution is made using 72.5 g of KNO3 diluted to a total solution volume of 2.00 L. Calculate the molarity, mola

Sonja [21]

Answer:

The molarity is 0.359 $\frac{moles}{L}$

The molality is 0.354 $\frac{moles}{kg}$

The mass percent of the solution es 3.45%

Explanation:

Molarity is a unit of concentration that indicates the amount of moles of solute that appear dissolved in each liter of the mixture. It is determined by:

$Molarity (M)=\frac{number of moles of solute}{volume}$

Being:

K: 39 g/mole
N: 14 g/mole
O: 16 g/mole

The molar mass of KNO₃ is:

KNO₃= 39 g/mole + 14 g/mole + 3*16 g/mole= 101 g/mole

You can apply the following rule of three: if 101 grams of KNO₃ are present in 1 mole, 72.5 grams in how many moles are present?

$moles of KNO_{3}=\frac{72.5 grams*1 mole}{101 grams}$

moles of KNO₃= 0.718

So you have:

moles of KNO₃= 0.718
volume= 2 L

Applying this quantity in the definition of molarity:

$molarity=\frac{0.718 moles}{2 L}$

Molarity= 0.359 $\frac{moles}{L}$

The molarity is 0.359 $\frac{moles}{L}$

Molality is a way of measuring the concentration of solute in solvent and indicates the amount of moles of solute in each kilogram of solvent.

Then the molality is calculated by:

$Molality=\frac{moles of solute}{mass of solvent in kilograms}$

Density is defined as the property that matter, whether solid, liquid or gas, has to compress in a given space. That is, it is the amount of mass per unit volume. So, if the density of 1.05 g / mL for the solution indicates that in 1 mL of solution there are 1.05 grams of solution, in 2000 mL (where 2L = 2000 mL, because 1 L = 1000mL) how much mass is there?

$mass=\frac{2000 mL*1.05 grams}{1 mL}$

mass= 2100 grams

Since mass solution = mass water + mass KNO₃

then mass water = mass solution - mass KNO₃

Being mass solution 2100 grams and mass KNO₃ 72.5 grams, and replacing you get: mass water= 2100 grams - 72.5 grams

mass water= 2,027.5 grams

Then, being:

moles of KNO₃= 0.718
mass of solvent in kilograms= 2.0275 kg (being 2,027.5 grams= 2.0275 kilograms because 1,000 grams= 1 kilogram)

Replacing in the definition of molality:

$molality=\frac{0.718 moles}{2.0275 kg}$

molality= 0.354 $\frac{moles}{kg}$

The molality is 0.354 $\frac{moles}{kg}$

The mass percent of a solution is the number of grams of solute per 100 grams of solution. Then the mass percent is the mass of the element or solute divided by the mass of the compound or solute and the result of which is multiplied by 100 to give a percentage.

$mass percent=\frac{mass of solute}{mass of solution} *100$

So, in this case:

$mass percent=\frac{72.5 grams}{2100 grams} *100$

mass percent= 3.45 % KNO₃ by mass

The mass percent of the solution es 3.45%

3 0

2 years ago

A glass cylinder contains 2 gases at a pressure of 106 kPa. If one gas is at 7 kPa, what is the pressure of attributed to the ot

Ivan

Answer:

b) 99 kPa

Explanation:

According to Daltons law of partial pressure, the total pressure of a mixture of two or more non reactive gases is the sum of their individual pressures. Let the total pressure of a mixture of n number of gases be $P_{total}$ and their individual pressure be $P_1,P_2,P_3,\ .\ .\ .\ ,\ P_n$ , According to Daltons partial pressure law:

$P_{total}=P_1+P_2+P_3+.\ .\ .+P_n$

Since A glass cylinder contains 2 gases at a pressure of 106 kPa, therefore n = 2. Also one gas ( $P_1$ ) is at 7 kPa. Using Daltons partial pressure law:

$P_{total}=P_1+P_2+P_3+.\ .\ .+P_n\\P_{total}=P_1+P_2\\106\ kPa=7\ kPa+P_2\\P_2=106\ kPa-7\ kPa\\P_2=99\ kPa$

7 0

3 years ago