Answer:A cup of household bleach changes the color of your favorite T-shirt from purple to pink. - chemical change
Water vapor in your exhaled breath condenses in the air on a cold day.- physical change
Plants use carbon dioxide from the air to make sugar.- chemical change
Butter melts when placed in the Sun- physical change
Explanation:
A chemical change leads to the formation of a new substance and is not easily reversible. A physical change does not lead to the formation of a new substance and is easily reversible. Physical changes include condensation, melting,etc while a chemical change is a chemical reaction.
<u>Answer:</u> The correct answer is Option A, Option B and Option D.
<u>Explanation:</u>
Molecular compound are defined as the compounds which are formed by the sharing of electrons between the atoms. They are also known as covalent compounds. They are of two types:
- <u>Polar covalent compound:</u> This compound is formed when difference in electronegativity between the atoms is present. When atoms of different elements combine, it results in the formation of polar covalent bond. For Example: etc..
- <u>Non-polar covalent compound:</u> This compound is formed when there is no difference in electronegativity between the atoms. When atoms of the same element combine, it results in the formation of non-polar covalent bond. For Example: etc..
We know that: Like dissolves like. This means that polar solvent will dissolve polar molecules and non-polar solvent will dissolve non-polar molecules
Water is a polar compound. So, it will dissolve only polar molecules.
The given substance 'X' is a molecular compound. It may be polar or non-polar.
So, it may be soluble in water or may not be soluble.
Electrolyte are defined as the compound which conduct electricity when dissolved in water. They conduct electricity because of the ions they dissociate into.
Thus, substance 'X' is not an electrolyte.
Hence, the correct answer is Option A, Option B and Option D.
Substances can change state, usually when they are heated or cooled. For example, liquid water turns into steam when it is heated enough, and it turns into ice when it is cooled enough. ... The closeness, arrangement and motion of the particles in a substance change when it changes state.
Answer:
Molecular formula => C₃H₈O₃
Explanation:
From the question given above, the following data were obtained:
Carbon (C) = 39.12%
Hydrogen (H) = 8.75%
Oxygen (O) = 51.12%
Molar mass of compound = 92.09 g/mol
Molecular formula =?
Next, we shall determine the empirical formula of the compound. This can be obtained as follow:
C = 39.12%
H = 8.75%
O = 51.12%
Divide by their molar mass
C = 39.12 / 12 = 3.26
H = 8.75 / 1 = 8.75
O = 51.12 / 16 = 3.195
Divide by the smallest
C = 3.26 / 3.195 = 1
H = 8.75 / 3.195 = 2.7
O = 3.195 / 3.195 = 1
Thus, the empirical formula is CH₂.₇O
Finally, we shall determine the molecular formula of the compound. This can be obtained as follow:
Empirical formula = CH₂.₇O
Molar mass of compound = 92.09 g/mol
Molecular formula =?
Molecular formula = Empirical formula × n
Molecular formula = [CH₂.₇O]ₙ
92.09 = [12 + (2.7×1) + 16] × n
92.09 = 30.7n
Divide both side by 30.7
n = 92.09 / 30.7
n = 3
Molecular formula = [CH₂.₇O]ₙ
Molecular formula = [CH₂.₇O]₃
Molecular formula = C₃H₈O₃
Answer:
Option (D)
Explanation:
In a nuclear power plant, the reactor core is comprised of various fuel assemblies. The nuclear fission takes place inside the core of the reactor, as a result of which the heat is produced immensely. This heat energy allows the water to boil and produces stream, which forces the blades of the turbines to rotate. This continuous rotation of the turbine blades ultimately generates electricity
It is one of the efficient methods as it is cheap, creates no pollution but it produces radioactive waste which is difficult to dispose of.
Thus, the excess heat in a nuclear power plant is used to rotate the turbines and produce electricity.
Hence, the correct answer is option (D).