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3 years ago

How do you think chemical change is defined?

1 answer:

8 0

A chemical change happens when one chemical substance is transformed into one or more different substances, such as when iron becomes rust. Chemical changes occur through the process of chemical reactions, and the resulting substances have different properties because their atoms and molecules are arranged differently.

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Complete and balance the precipitation reaction. include physical states in your answer. click here for solubility rules. cucl2

stiks02 [169]

Hey there!:

Balanced equation:

Na2CO3(aq) + CuCl(aq) -> CuCO3(s) + 2 NaCl(aq)

Since CuCO3 is more stable so displacement and precipitation will take place.

Hope that helps!

4 0

4 years ago

Read 2 more answers

A galaxy is a group of billions of stars, star systems, star clusters, dust and gas bound

Katen [24]

Answer:

Gravity (B)

Explanation:

In reality this is an easy question to answer, but i'll explain it. The black hole in the center of whatever galaxy is creating an insane amount of gravity, pulling everything towards it and thus keeping it together.

7 0

3 years ago

Read 2 more answers

The equilibrium-constant expression for a reaction written in one direction is the __________ of the one for the reaction writte

VLD [36.1K]

Answer:

reciprocal

Explanation:

The equilibrium constant for an equilibrium reaction is the ratio of the equilibrium constant for the forward reaction, Kf, to the equilibrium constant for the reverse reaction, Kr:

For A ⇄ B

The forward reaction is: A → B, with rate constant is Kf = K₁ and
The reverse reaction is: B → A, with rate constant Kr = K₂

$K_{eq}=\dfrac{K_f}{K_r}=\dfrac{K_1}{K_2}$

When you write the reaction in the other reaction, the forward and the reverse reaction are exchanged:

For B ⇄ A

The forward reaction is B → A, with rate constant Kf = K₂
The reverse reaction is A → B, with rate constant Kr = K₁

$K'_{eq}=\dfrac{K_f}{K_r}=\dfrac{K_2}{K_1}$

As you see:

$K'_{eq}=\dfrac{1}{K_{eq}}$

Thus, the equilibrium-constant expression for a reaction written in one direction is the  reciprocal___ of the one for the reaction written for the reverse direction.

8 0

4 years ago

Where do the numbers in a stoichiometry mole ratio come from?

erik [133]

it is defined as the ratio of moles of one substance to the moles of another substance in a balanced equation. To determine the mole ratio between two substances, all you need to do is look at the balanced equation for the coefficients in front of the substances you are interested in.

5 0

3 years ago

Potassium chloride (KCl) is sometimes used to treat low blood potassium levels. Calculate the concentration of a saturated solut

brilliants [131]

Molarity is the most convenient way to express concentration.

Mathematically, molarity is expressed as $\frac{\text{mass of solute(g)}}{\text{gram molecular weight X Volume of solution (l)}}$

In present case,
mass of solute (KCl) = 36 g
molecular weight of KCl = 74.55 g/mol
volume of solution = 100 ml = 0.1 l

∴ Molarity = $\frac{36}{74.55X0.1}$
= 4.829 M
Thus, conc. of saturated KCl at 20 oC is 4.829 M

7 0

3 years ago