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2 years ago

True or false 4 questions help please!

Chemistry

1 answer:

Alekssandra [29.7K]2 years ago

5 0

Answer:

Explanation:

True or false 4 questions help please!

Most mixtures are not physical changes.

True

False FALSE when I add solid NaCl salt to water I no longer have a solid salt, I have a solution of sodium and chlorid ions in liquid water. this is physical change

Chemical Changes do not create a new substance.

True

False FALSE 0ne of the proofs that you have a chemical change is the presence of a new substance

Fire is an example of a Chemical Change.

True TRUE fire is oxygen reacting wiIh mattter to form new compounds

False

Explosions are not chemical changes.

It depends on the explosion if I blow up a balloon until it POPS!! that is physical chame. If I light a firecracker and it explodes, that is a chemical change of oxygen reacting with hot gunpowder

A change in color and odor are both examples of chemical changi

I would rewrite the question as

A change in color and odor both INDICATE a chemical change

and that is

True TRUE

False

True Fire is an example of a Chemical Change.

True

False

Explosions are not chemical changes.

True

False

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Write a procedure for "how to crack an egg" in cooking. You must have at least 3 steps. The format of your procedure is more imp

Nataly_w [17]

$▪▪▪▪▪▪▪▪▪▪▪▪▪ {\huge\mathfrak{Answer}}▪▪▪▪▪▪▪▪▪▪▪▪▪▪$

Here's the procedure to Crack an egg ~

Step 1 ~

Hold the egg in your hand and tap it on a firm surface

Step 2 ~

Gently pull the shells apart

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And release the yolk in the bowl

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2 years ago

Be sure to answer all parts. Consider the formation of ammonia in two experiments. (a) To a 1.00−L container at 727°C, 1.30 mol

Sonbull [250]

Answer: The value of $K_c$ for $2NH_3(g)\rightleftharpoons N_2(g)+3H_2(g)$ reaction is $5.13\times 10^2$

Explanation:

We are given:

Initial moles of nitrogen gas = 1.30 moles

Initial moles of hydrogen gas = 1.65 moles

Equilibrium moles of ammonia = 0.100 moles

Volume of the container = 1.00 L

For the given chemical equation:

$N_2(g)+3H_2(g)\rightleftharpoons 2NH_3(g)$

Initial: 1.30 1.65

At eqllm: 1.30-x 1.65-3x 2x

Evaluating the value of 'x'

$\Rightarrow 2x=0.100\\\\\Rightarrow x=0.050mol$

The expression of $K_c$ for above equation follows:

$K_c=\frac{[NH_3]^2}{[N_2]\times [H_2]^3}$

Equilibrium moles of nitrogen gas = $(1.30-x)=(1.30-0.05)=1.25mol$

Equilibrium moles of hydrogen gas = $(1.65-x)=(1.65-0.05)=1.60mol$

Putting values in above expression, we get:

$K_c=\frac{(0.100)^2}{1.25\times (1.60)^3}\\\\K_c=1.95\times 10^{-3}$

Calculating the $K_c'$ for the given chemical equation:

$2NH_3(g)\rightleftharpoons N_2(g)+3H_2(g)$

$K_c'=\frac{1}{K_c}\\\\K_c'=\frac{1}{1.95\times 10^{-3}}=5.13\times 10^2$

Hence, the value of $K_c$ for $2NH_3(g)\rightleftharpoons N_2(g)+3H_2(g)$ reaction is $5.13\times 10^2$

8 0

3 years ago

Read 2 more answers

Draw a structural formula for the alkene you would use to prepare the alcohol shown by hydroboration/oxidation.

Nastasia [14]

Answer:

See explanation

Explanation:

The question is incomplete because the image of the alcohol is missing. However, I will try give you a general picture of the reaction known as hydroboration of alkenes.

This reaction occurs in two steps. In the first step, -BH2 and H add to the same face of the double bond (syn addition).

In the second step, alkaline hydrogen peroxide is added and the alcohol is formed.

Note that the BH2 and H adds to the two atoms of the double bond. The final product of the reaction appears as if water was added to the original alkene following an anti-Markovnikov mechanism.

Steric hindrance is known to play a major role in this reaction as good yield of the anti-Markovnikov like product is obtained with alkenes having one of the carbon atoms of the double bond significantly hindered.

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3 years ago

As two objects that are oppositely charged are brought together which will happen

BaLLatris [955]

Opposites attract, like for example magnets, one is positive and the other is negatively charged, they will attract

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3 years ago

Calculate the volume which 1.00 mole of a gas occupies at 1 atm and 298K?

elena-14-01-66 [18.8K]

Answer:

25.45 Liters

Explanation:

Using Ideal Gas Law PV = nRT => V = nRT/P

V = (1mole)(0.08206Latm/molK)(298K)/(1atm) = 25.45 Liters

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2 years ago