All categories

3 years ago

Answer the questions below:

Chemistry

1 answer:

Allushta [10]3 years ago

4 0

Answer:

1. some thing that has matter is an apple, a person,a table. things that does 2.not Light.,Sound.,Heat.Energy.Gravity.Time.A Rainbow.Love.

3. Physical changes only change the appearance of a substance, not its chemical composition. Chemical changes cause a substance to change into an entirely substance with a new chemical formula. Chemical changes are also known as chemical reactions.

4.A chemical reaction is usually accompanied by easily observed physical effects, such as the emission of heat and light, the formation of a precipitate, the evolution of gas, or a color change. Absolute confirmation of a chemical change can only be validated by chemical analysis of the products!

5.Precipitate: In chemistry, a solid formed by a change in a solution, often due to a chemical reaction or change in temperature that decreases solubility of a solid. In meteorology a precipitate is liquid or solid water (rain, snow, etc.) falling from the sky.

6.n simple terms, the endothermic reactions absorb energy from the surrounding that is in the form of heat. On the other hand, an exothermic reaction releases energy into the surrounding of the system.

hope this help plz give me a thxs and brainlyest and a five star thx and you welcome let me know if this helped

Explanation:

You might be interested in

A piston is pressurized to 15.5 psi at 405 K. If the piston compresses the air, from 8.98 L to 7.55 L, and the pressure drops to

masya89 [10]

Answer:

239.45 K

Explanation:

Ideal gas law formula is P1V1T2=P2V2T1

Rearrange that to get...

T2=T1P2V2/P1V1

Fill in the values and solve.

7 0

3 years ago

How ph relate with poh

mylen [45]

<span>The "p" in pH and pOH stands for "negative logarithm of" and is used to make it easier to work with extremely large or small values. pH and pOH are only meaningful when applied to aqueous (water-based) solutions. </span>

3 0

3 years ago

Read 2 more answers

in a mixture of 1.90 mol of gas, 0.85 mol are nitrogen (n2) molecules. what is the mole fraction of n2 in this mixture?

Nostrana [21]

0.447 is the mole fraction of Nitrogen in this mixture.

mole fraction of nitrogen= moles of nitrogen/total moles

mole fraction of nitrogen=0.85/1.90

mole fraction of nitrogen=0.447

The product of the moles of a component and the total moles of the solution yields a mole fraction, which is a unit of concentration measurement. Because it is a ratio, mole fraction is a unitless statement. The sum of the components of the mole fraction of a solution is one. In a mixture of 1 mol benzene, 2 mol carbon tetrachloride, and 7 mol acetone, the mole fraction of the acetone is 0.7. This is computed by dividing the sum of the moles of acetone in the solution by the total number of moles of the solution's constituents:

To know more about mole fraction visit : brainly.com/question/8076655

#SPJ4

4 0

1 year ago

In an aqueous solution of a certain acid the acid is 4.4% dissociated and the pH is 3.03. Calculate the acid dissociation consta

NeX [460]

Answer:

4.1x10⁻⁵

Explanation:

The dissociation of an acid is a reversible reaction, and, because of that, it has an equilibrium constant, Ka. For a generic acid (HA), the dissociation happens by:

HA ⇄ H⁺ + A⁻

So, if x moles of the acid dissociates, x moles of H⁺ and x moles of A⁻ is formed. the percent of dissociation of the acid is:

% = (dissociated/total)*100%

4.4% = (x/[HA])*100%

But x = [A⁻], so:

[A⁻]/[HA] = 0.044

The pH of the acid can be calcualted by the Handersson-Halsebach equation:

pH = pKa + log[A⁻]/[HA]

3.03 = pKa + log 0.044

pKa = 3.03 - log 0.044

pKa = 4.39

pKa = -logKa

logKa = -pKa

Ka = $10^{-pKa}$

Ka = $10^{-4.39}$

Ka = 4.1x10⁻⁵

4 0

3 years ago

Temperature measures how hot or cold something is compared to a reference point. Explain what is meant by reference point

cricket20 [7]

Hello.

A reference point means the point used to find or describe the location of something.

Hope this helped :).

8 0

3 years ago