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3 years ago

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How do you know if a reaction is exothermic? Enter your answer in the space provided

1 answer:

monitta3 years ago

3 0

Exothermic is a chemical reaction in which heat is released. Lighting a candle is an example of an exothermic because the flame is the heat being released.

You might be interested in

How many chlorine atoms are found in 8.3 moles of chlorine?

erik [133]

Answer:

5*10²⁴ chlorine atoms are found in 8.3 moles of chlorine.

Explanation:

Avogadro's Number or Avogadro's Constant is called the number of particles that make up a substance (usually atoms or molecules) and that can be found in the amount of one mole of said substance. Its value is 6.023*10²³ particles per mole. Avogadro's number represents a quantity without an associated physical dimension, so it is considered a pure number that allows describing a physical characteristic without an explicit dimension or unit of expression. Avogadro's number applies to any substance.

Then you can apply the following rule of three: if 1 mole of the compound contains 6.023 * 10²³ atoms, 8.3 moles of the compound how many atoms does it have?

$amount of atoms=\frac{8.3 moles*6.023*10^{23}atoms }{1 mole}$

amount of atoms≅ 5*10²⁴ atoms

<u><em>5*10²⁴ chlorine atoms are found in 8.3 moles of chlorine.</em></u>

4 0

3 years ago

Which compound contains a double bond?

just olya [345]

The answer would be ethane (C2H4)

7 0

3 years ago

The turnover number is defined as the maximum number of substrate molecules that can be converted into product molecules per uni

Nataliya [291]

Answer:

Explanation:

turn over number = R max / [E]t = K2

From given , R max = 249 * 10 ^ -6 mol. L^-1

T [E]t = 2.23 n mol. L^-1

= 2.23 * 10^-9 mol. L^-1

Putting values in above equation,

= 111.65 * 10^3 S^-1

Turn over number is maximum no of substrate molecule that can be converted into product molecules for unit time by enzyme molecule.

5 0

3 years ago

Exactly 1.0 mol N2O4 is placed in an empty 1.0-L container and is allowed to reach equilibriumdescribed by the equation N2O4(g)↔

Vilka [71]

Answer : The correct option is, (C) 1.1

Solution : Given,

Initial moles of $N_2O_4$ = 1.0 mole

Initial volume of solution = 1.0 L

First we have to calculate the concentration $N_2O_4$ .

$\text{Concentration of }N_2O_4=\frac{\text{Moles of }N_2O_4}{\text{Volume of solution}}$

$\text{Concentration of }N_2O_4=\frac{1.0moles}{1.0L}=1.0M$

The given equilibrium reaction is,

$N_2O_4(g)\rightleftharpoons 2NO_2(g)$

Initially c 0

At equilibrium $(c-c\alpha)$ $2c\alpha$

The expression of $K_c$ will be,

$K_c=\frac{[NO_2]^2}{[N_2O_4]}$

$K_c=\frac{(2c\alpha)^2}{(c-c\alpha)}$

where,

$\alpha$ = degree of dissociation = 40 % = 0.4

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

$K_c=\frac{(2c\alpha)^2}{(c-c\alpha)}$

$K_c=\frac{(2\times 1\times 0.4)^2}{(1-1\times 0.4)}$

$K_c=1.066\aprrox 1.1$

Therefore, the value of equilibrium constant for this reaction is, 1.1

4 0

3 years ago

How many grams of Na2CO3 must be dissolved into 155g of water to create a solution with a molarity of 8.20 mol/kg

zhannawk [14.2K]

Answer:

135g Na2CO3

Explanation:

I'm going to assume you mean Molality which is mol solute/kg solvent

Molarity would be mol soute/ L solution

we know we have 155g of water which is .155 kg

essentially we have the equation:

mol/kg = 8.20

we substitute .155 in for kg and get:

mol/.155 = 8.20

Solving this gives mol = 1.271

now we must convert to grams using the molar mass

Molar mass Na2CO3 = 106G/mol

so to cancel moles we multiply:

1.271mol x 106g/mol

= 135g

4 0

3 years ago