When does phenolphthalein turn pink?a) in the presence of a base
b) in the presence of an acid
c) when it is in a neutral solution
d) when it is reacting with a metal
Answers
Answer is: a) in the presence of a base.
Phenolphthalein is colorless in acidic solutions and pink in basic solutions.
Acid-base indicators are usually weak acids or bases and they are chemical detectors for hydrogen or hydronium cations.
Example for acid-base indicator is phenolphthalein (molecular formula C₂₀H₁₄O₄).
When solution turns phenolphthalein pink, it means it is basic (pH>7).
Final answer:
Phenolphthalein turns pink in the presence of a base.
Explanation:
Phenolphthalein turns pink in the presence of a base. It is a pH indicator that changes color depending on the acidity or alkalinity of a solution. In an acidic solution, phenolphthalein remains colorless, while in a basic solution, it turns pink.
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allowing particles to collect
clumping particles together
attracting the heat of the nebular cloud
Answers
Answer: Attracting the heat of the nebular cloud
Heat is lessened by interstellar dust through attraction of heat in the gas cloud. The nebular cloud’s heat, coming from radiation emitted by stars, is indirectly cooled down by dust through ionization and beams it towards space.
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B) diffraction.
C) reflection.
D) refraction.
Answers
The study of matter is called physics.
The correct answer to the question is option D which is refraction.
What is refraction?
- Refraction is the change in direction of a wave passing from one medium to another or from a gradual change in the medium.
- Refraction of light is the most commonly observed phenomenon, but other waves such as sound waves and water waves also experience refraction
According to the question, If you put a straw into a glass of water, the straw looks to be bent, although nothing has physically happened to the straw. The term that describes this property of light is called refraction.
Hence, the answer is Refraction.
For more information about the refraction, refer to the link:-
So, the answer would be: Refraction
Answers
Answer:
it becomes poisonous to the body
c. 480 g/cm3
b. 270 g/cm3
d. 48 g/cm3
Answers
Density = mass / volume
D = 360 g / 7.5 cm³
D = 48 g/cm³
answer D
hope this helps!
Answers
oxidation
hydrolysis
abrasion
Answers
Answer: The correct answer is oxidation.
Explanation:
Rust is a reddish-brown colored compound which is formed by the oxidation of Iron to form ferric oxide. The formula for this chemical compound is
Oxidation is defined as the reaction in which addition of oxygen takes place.
The reaction for the formation of rust is given by the equation, we get:
By Stoichiometry,
4 moles of iron metal reacts with 3 moles of oxygen gas to form 2 moles of ferric oxide.
Hence, the correct answer is oxidation.