Study HubHubPage 8/16Scan verified MCQs with the answer highlighted, then open explanations when you want the reasoning.
Read Mode
Atomic Structure
Isotopes of an element have the same number of ________?
Isotopes of an element have the same number of protons, which defines the element, but differ in the number of neutrons. Therefore, the correct answer is 'Protons'.
Read Mode
Chemical Formulas
What is the chemical formula for sodium carbonate?
The chemical formula for sodium carbonate is Na2CO3, which consists of two sodium (Na) atoms, one carbon (C) atom, and three oxygen (O) atoms. This is the correct and widely accepted formula for sodium carbonate.
Read Mode
Alcohols
What is the other name of ethyl alcohol?
Ethyl alcohol is commonly known as ethanol, which is its systematic name. The other options are incorrect: Ethene is an alkene, Propyle is a misspelling of propyl (a different compound), and 'none' is not a valid chemical name.
Read Mode
Atomic Structure
Elements which have the same number of protons but different numbers of neutrons are called ________?
Elements with the same number of protons but different numbers of neutrons are called isotopes. This is because isotopes are variants of the same element differing only in neutron count, while protons define the element itself.
Read Mode
Chemical Symbols
Which of the following letters does not represent an element in the periodic table?
The letter 'J' is not used as a chemical symbol for any element in the periodic table, whereas 'X' (Xenon), 'K' (Potassium), and 'N' (Nitrogen) are valid element symbols.
Read Mode
Gas Laws
Which law states that "equal volumes of all gases, at the same temperature and pressure, have the same number of molecules?"
Avogadro's law states that equal volumes of all gases, at the same temperature and pressure, contain the same number of molecules. This principle is fundamental in understanding gas behavior.
Read Mode
Chemical And Physical Changes
Which one of the following represents a chemical change?
Heating mercuric oxide powder causes it to decompose into mercury and oxygen, which is a chemical change. The other options involve physical changes or no chemical change.
Read Mode
Gas Laws
Which law states that the volume of a given amount of gas held at constant pressure is directly proportional to the Kelvin temperature?
Charles' Law states that the volume of a given amount of gas held at constant pressure is directly proportional to its Kelvin temperature. This means as temperature increases, volume increases proportionally, provided pressure remains constant.
Read Mode
Industrial Chemistry
How is ammonia synthesized?
Ammonia is synthesized industrially by the Haber process, which combines nitrogen and hydrogen gases under high temperature and pressure in the presence of a catalyst. The other options are unrelated to ammonia synthesis.
Read Mode
Chemical Bonding
Which of the following bonds are weakest in nature?
Hydrogen bonds are weaker than covalent bonds such as single, double, and triple bonds. Covalent bonds involve sharing of electrons and are stronger, while hydrogen bonds are intermolecular forces and thus weaker in nature.