2021 - JAMB Chemistry Past Questions and Answers - page 4
A chemical process in which there is a gain of electrons is known as___?
Sublimation
Reduction
Oxidation
Distillation
Redox is a type of chemical reaction in which the oxidation states of the substrate change. Oxidation is the loss of electrons or an increase in the oxidation state, likewise, reduction is the gain of electrons or a decrease in the oxidation state. More
The reactions involving simultaneous oxidation and reduction?
Automatic reactions
Alternate reactions
Reduction agency
Redox reactions
Redox is a type of chemical reaction in which the oxidation states of the substrate change. Oxidation is the loss of electrons or an increase in the oxidation state, likewise, reduction is the gain of electrons or a decrease in the oxidation state. More
A binary compound of oxygen with another element is referred to as?
Oxide
Element
Carbon
Nitrogen
An oxide is a chemical compound that contains at least one oxygen atom and one other element in its chemical formula.
The process or act of extracting a metal from its ore and refining it is called?
Extraction
Metal mining
Mettallurgy
Prospecting
Metallurgy is the art and science of extracting metals from their ores and modifying the metals for use. It is also defined as a domain of materials science and engineering that studies the physical and chemical behaviour of metallic elements, their inter-metallic compounds, and their mixtures, which are known as alloys. More.
The compounds made up of only carbon and hydrogen are called?
Carbon compounds
Hydrocarbons
Atoms
Carbon hydrolysis
In organic chemistry, a hydrocarbon is an organic compound consisting entirely of hydrogen and carbon. Hydrocarbons are examples of group 14 hydrides. Hydrocarbons are generally colourless and hydrophobic, and their odours are usually weak or exemplified by the odours of gasoline and lighter fluid. Wikipedia
Natural sources of hydrocarbon are coal, natural gas and petroleum.
Which of the following is not a physical property of monosaccharides?
Monosaccharides get charred when heated
Monosaccharides are water-soluble, sweet substances
They are highly vital to the exploration of metals
They can be reduced to sugar alcohols
- Monosaccharides Form a black residue of carbon when dehydrated
- they have a sweet taste
- they are reducing sugars.
- pure monosaccharides are water-soluble, white, crystalline solids
In the troposphere, the two types of pollutants are?
Gaseous and particulate pollutants
Carbon and metallic pollutants
Natural and man-made pollutants
Sulphuric and nitrogenous pollutants
The troposphere is the first and lowest layer of the atmosphere of the Earth, and contains 75% of the total mass of the planetary atmosphere, 99% of the total mass of water vapour and aerosols, and is where most weather phenomena occur. More
The gaseous and particulate pollutants in the troposphere include:
Gaseous Pollutants: The oxides of nitrogen and sulphur, ozone, hydrocarbons, and several other oxidants in this category.
Particulate Matter: viable particulates such as microorganisms like fungi and bacteria, non-viable particulate matter such as smoke.
The molar enthalpy change accompanying the removal of an electron from a gas phase atom or ion in its ground state is called?
Electron gain enthalpy
Ionization enthalpy
Enthalpy change
Enthalpic gas removal
The ionization enthalpy of an element is the amount of energy required to remove an electron from an isolated gaseous atom in its gaseous state.
The fourteen elements (atomic numbers 90-103) after actinium are called?
Actinoids
Nucleotides
Pre-actinum elements
Atomic elements
The actinide or actinoid series encompasses the 15 metallic chemical elements with atomic numbers from 89 to 103, actinium through lawrencium. The actinide series derives its name from the first element in the series, actinium. More
The process by which salt and water reacted in a limited way to form an acid or a base is?
Neutral process
Basic acidic process
Hydrolysis
Sublimation
Salt hydrolysis is a reaction in which one of the ions from a salt reacts with water, forming either an acidic or basic solution.