Explanation:A chemical reaction is the process in which atoms present in the starting substances rearrange to give new chemical combinations present in the substances formed by the reaction. These starting substances of a chemical reaction are called the reactants, and the new substances that result are called the products.

7 0

3 years ago

A 1.85 kg textbook is sitting on a bookshelf 2.23 m above the floor. How much potential energy does it have?

neonofarm [45]

Answer:

$\boxed {\boxed {\sf 40.4299 \ Joules}}$

Explanation:

Potential energy is energy due to position. It is the product of mass, height, and acceleration due to gravity.

$PE= m \times g \times h$

The mass of the textbook is 1.85 kilograms. Assuming this is on Earth, the acceleration due to gravity is 9.8 meters per square second. The height is 2.23 meters.

m= 1.85 kg
g= 9.8 m/s²
h= 2.23 m

Substitute the values into the formula.

$PE = 1.85 \ kg \times 9.8 \ m/s^2 \times 2.23 \ m$

Multiply the first 2 numbers together.

$PE=18.13 \ kg*m/s^2 *2.23 \ m$

Multiply again.

$PE= 40.4299 \ kg*m^2/s^2$

1 kilogram square meter per square second (1 kg*m²/s²) is equal to 1 Joules (J)
Our answer of 40.4299 kg*m²/s² is equal to 40.4299 J

$PE= 40.4299 \ J$

The textbook has <u>40.4299 Joules of potential energy.</u>

7 0

3 years ago

What is calorimetry

Masja [62]

Answer:

The science or act of measuring changes in state variables of a body for the purpose of deriving the heat transfer associated with changes of its state due, for example, to chemical reactions, physical changes, or phase transitions under specified constraints.

Explanation:

5 0

4 years ago

Check all that apply.

White raven [17]

Answer:

4 for C in CH4

+4 for C in CO2

-2 for O in all substances

+1 for H in both CH4 and H2O

option 1,2,3 and 4 are correct. Option 5 is not correct

Explanation:

Step 1: Data given

Oxidation number of H = +1

Oxidation number of O = -2

Step 2: The balanced equation

CH4(g) + 2O2(g) → CO2(g) + 2H2O(g)

Step 3: The oxidation numbers

-4 for C in CH4

⇒ Oxidation number of H = +1

⇒ 4x +1 = +4

C has an oxidation number of -4

This is correct.

+4 for C in CO2

⇒ Oxidation number of O = -2

⇒ 2x -2 = -4

C has an oxidation number of +4

This is correct.

-2 for O in all substances

⇒ this is correct, the oxidation number of O is always -2 (except in H2O2 and Na2O2)

This is correct.

+1 for H in both CH4 and H2O

⇒ this is correct, the oxidation number of H is always +1 (except in metal hydrides).

This is correct.

+4 for O in H2O

⇒ Oxidation number of H = +1

⇒ 2x +1 = +2

The oxidation number of O is -2

This is not correct

5 0

3 years ago