The boiling point is always higher than the melting point
The melting point is always higher than the boiling point
The melting and boiling points are always the same for all substances
The melting and boiling points can vary depending on the substance
Correct answer is D
The melting and boiling points are specific physical properties of each substance and can vary depending on the nature of the substance. Different substances have different melting and boiling points, which are determined by the strength of the intermolecular forces and the molecular structure of the substance.
What is the IUPAC name for the compound CCl\(_4\)?
Tetrahydrochloride
Tetrachloromethane
Carbon tetrachloride
Chloroform
Correct answer is B
The compound CCl\(_4\) is a chlorinated hydrocarbon with a central carbon atom and four chlorine atoms attached to it. According to IUPAC rules, the correct name for this compound is "tetrachloromethane."
The lanthanides and actinides are located in which block of the periodic table?
P-block
S-block
F-block
D-block
Correct answer is C
The lanthanides and actinides are located in the f-block of the periodic table, which is a separate row placed at the bottom of the main table. These elements are also known as the inner transition metals.
Which of the following is a characteristic property of acids?
Turn litmus paper blue
Bitter taste
pH value above 7
React with metals to produce hydrogen gas
Correct answer is D
Acids are substances that can donate protons (H+) in aqueous solutions. When acids react with certain metals, they can release hydrogen gas (H2) as one of the products. This is a common behavior of many acids and can be used to distinguish them from other substances.
Which of the following is an example of a primary cell?
Alkaline battery
Nickel-cadmium battery
Lead-acid battery
Lithium-ion battery
Correct answer is A
Primary cells are non-rechargeable batteries, and the alkaline battery is a common example of a primary cell