CIDESCO EXAM PREP QUESTIONS AND
ANSWERS GRADED A+ 2025/2026
I Biological and non-biological substances both need oxygen for their existence. II The human
body consists only of biological substances. - ANS I is correct and II is incorrect
Characteristics of life include: - ANS growth and metabolism
Examples of synthetic substances are: - ANS plastics and silicones
Examples of organic biological substances are: - ANS carbohydrates and fats
Examples of mineral substances are: - ANS paraffins and petroleum
Matter is everything that: - ANS occupies space and has weight
The three forms of matter are solids, liquids and: - ANS gases
What property does all matter have? - ANS All matter has weight
Condensation is the change of matter from: - ANS a gas to a liquid
Vapourisation is the change of matter from: - ANS liquid to a gas
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,Melting is the change of matter from: - ANS a solid to a liquid
Sublimation is the change of matter from: - ANS a solid to a gas
Condensation is: - ANS the change of a vapour to a liquid
The alteration of the properties of matter without the formation of any new substance is called
a/an: - ANS physical change
The immediate change of a solid into a vapour is called: - ANS sublimation
An example of a single-celled cellular organism is: - ANS a bacterium
I. A micro-organism is the smallest part of the human body. II All micro-organisms need
nutrients for their existence. - ANS I is incorrect and II is correct
Examples of bacteria are: - ANS bacilli and cocci
I. Every living organism needs some non-biological substances for it's existence. II. All non-
biological substances are found as minerals in the earth. - ANS I is correct and II is incorrect
Science deals mainly with: - ANS physics and chemistry
The study of the structure of the body is called: - ANS anatomy
The study of the functions of living organisms is: - ANS physiology
2 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
,I Anatomy is a very important science in the field of biology. II Anatomy is the science which
deals with the functions of the human body. - ANS I is correct and II is incorrect
I Physiology is a very important science in the field of biology. II Physiology is the science which
deals with the functions of the body. - ANS I and II are both correct
Which one of the following belongs to the science of chemistry? - ANS The alteration of the
structure of molecules
I Chemical reactions only take place outside and not inside a living organism. II The structure of
molecules change during chemical reactions. - ANS I is incorrect and II is correct
The field of physics includes: - ANS heat and electricity
Which one of the following belongs to the field of physics? - ANS Sound, electricity and heat
The field of physics includes: - ANS the science of electricity
An anion is: - ANS A negatively charged atom
An anion is: - ANS a negatively charged chloride atom (CI-)
A cation is: - ANS A positively charged sodium atom (Na+)
An electrolyte is: - ANS A substance which, dissolved in water, splits into ions
Examples of electrolytes are: - ANS acids and salts
An example of an electrolyte is: - ANS salt-solution
3 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
, An acid is an electrolyte because: - ANS it can conduct an electric current
An example of an inorganic acid is: - ANS sulphuric acid
An alkali must contain: - ANS metal atoms and hydroxyl group(s) (OH)
An example of an alkaline substance is: - ANS soap
If a metal-oxide is dissolved in water it forms: - ANS an alkali
The pH scale is used to measure the degree of acidity or: - ANS alkalinity
pH can be decreased by: - ANS increasing hydrogen-ions
The letter p in pH means: - ANS potential
pH is: - ANS the number of free H-ions in solution
If the pH of a solution is between 5 and 7, the solution is a: - ANS weak acid
If the pH of a solution is between 1 and 3 the solution is a: - ANS strong acid
If the pH of a solution is between 7 and 9 the solution is a: - ANS weak alkali
If the pH of a solution is between 12 and 14 the solution is: - ANS strong alkali
The pH of distilled water is: - ANS 7
4 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
ANSWERS GRADED A+ 2025/2026
I Biological and non-biological substances both need oxygen for their existence. II The human
body consists only of biological substances. - ANS I is correct and II is incorrect
Characteristics of life include: - ANS growth and metabolism
Examples of synthetic substances are: - ANS plastics and silicones
Examples of organic biological substances are: - ANS carbohydrates and fats
Examples of mineral substances are: - ANS paraffins and petroleum
Matter is everything that: - ANS occupies space and has weight
The three forms of matter are solids, liquids and: - ANS gases
What property does all matter have? - ANS All matter has weight
Condensation is the change of matter from: - ANS a gas to a liquid
Vapourisation is the change of matter from: - ANS liquid to a gas
1 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
,Melting is the change of matter from: - ANS a solid to a liquid
Sublimation is the change of matter from: - ANS a solid to a gas
Condensation is: - ANS the change of a vapour to a liquid
The alteration of the properties of matter without the formation of any new substance is called
a/an: - ANS physical change
The immediate change of a solid into a vapour is called: - ANS sublimation
An example of a single-celled cellular organism is: - ANS a bacterium
I. A micro-organism is the smallest part of the human body. II All micro-organisms need
nutrients for their existence. - ANS I is incorrect and II is correct
Examples of bacteria are: - ANS bacilli and cocci
I. Every living organism needs some non-biological substances for it's existence. II. All non-
biological substances are found as minerals in the earth. - ANS I is correct and II is incorrect
Science deals mainly with: - ANS physics and chemistry
The study of the structure of the body is called: - ANS anatomy
The study of the functions of living organisms is: - ANS physiology
2 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
,I Anatomy is a very important science in the field of biology. II Anatomy is the science which
deals with the functions of the human body. - ANS I is correct and II is incorrect
I Physiology is a very important science in the field of biology. II Physiology is the science which
deals with the functions of the body. - ANS I and II are both correct
Which one of the following belongs to the science of chemistry? - ANS The alteration of the
structure of molecules
I Chemical reactions only take place outside and not inside a living organism. II The structure of
molecules change during chemical reactions. - ANS I is incorrect and II is correct
The field of physics includes: - ANS heat and electricity
Which one of the following belongs to the field of physics? - ANS Sound, electricity and heat
The field of physics includes: - ANS the science of electricity
An anion is: - ANS A negatively charged atom
An anion is: - ANS a negatively charged chloride atom (CI-)
A cation is: - ANS A positively charged sodium atom (Na+)
An electrolyte is: - ANS A substance which, dissolved in water, splits into ions
Examples of electrolytes are: - ANS acids and salts
An example of an electrolyte is: - ANS salt-solution
3 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
, An acid is an electrolyte because: - ANS it can conduct an electric current
An example of an inorganic acid is: - ANS sulphuric acid
An alkali must contain: - ANS metal atoms and hydroxyl group(s) (OH)
An example of an alkaline substance is: - ANS soap
If a metal-oxide is dissolved in water it forms: - ANS an alkali
The pH scale is used to measure the degree of acidity or: - ANS alkalinity
pH can be decreased by: - ANS increasing hydrogen-ions
The letter p in pH means: - ANS potential
pH is: - ANS the number of free H-ions in solution
If the pH of a solution is between 5 and 7, the solution is a: - ANS weak acid
If the pH of a solution is between 1 and 3 the solution is a: - ANS strong acid
If the pH of a solution is between 7 and 9 the solution is a: - ANS weak alkali
If the pH of a solution is between 12 and 14 the solution is: - ANS strong alkali
The pH of distilled water is: - ANS 7
4 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
