Which gas is most abundant in the Earth’s atmosphere?
a) Oxygen
b) Nitrogen
c) Carbon dioxide
d) Hydrogen
What is the chemical symbol for the element gold?
a) Au
b) Ag
c) Fe
d) Hg
Which of the following is a primary color of light?
a) Red
b) Yellow
c) Green
d) Orange
What is the boiling point of water in degrees Celsius?
a) 0°C
b) 100°C
c) 212°C
d) 273°C
Which of the following is an example of a renewable energy source?
a) Coal
b) Natural gas
c) Solar power
d) Nuclear power
What is the basic unit of electric current?
a) Volt
b) Ampere
c) Ohm
d) Watt
Which of the following is not a type of simple machine?
a) Lever
b) Pulley
c) Screw
d) Battery
What is the largest organ in the human body?
a) Heart
b) Liver
c) Brain
d) Skin
Which planet is known as the "Red Planet”?
a) Mars
b) Venus
c) Jupiter
d) Saturn
What is the chemical formula for table salt?
a) NaCl
b) H2O
c) CO2
d) C6H12O6
What is the process by which plants convert sunlight into energy?
a) Photosynthesis
b) Respiration
c) Transpiration
d) Germination
Which of the following is a greenhouse gas responsible for climate change?
a) Oxygen
b) Nitrogen
c) Methane
d) Argon
Which of the following is the primary function of white blood cells?
a) Carrying oxygen
b) Fighting infections
c) Clotting blood
d) Transporting nutrients
What is the main component of the Earth’s core?
a) Iron
b) Oxygen
c) Silicon
d) Hydrogen
Which of the following is responsible for carrying signals between different parts of the body?
a) Nerves
b) Hormones
c) Enzymes
d) Antibodies
What is the formula for calculating density?
a) Mass × Volume
b) Volume × Temperature
c) Mass ÷ Volume
d) Mass + Volume
What is the main function of the ozone layer in the Earth’s atmosphere?
a) Absorbing ultraviolet radiation
b) Regulating temperature
c) Producing oxygen
d) Generating rainfall
Which of the following is a primary source of vitamin C?
a) Oranges
b) Milk
c) Eggs
d) Spinach
What type of energy transformation occurs in a toaster?
a) Electrical to thermal
b) Thermal to electrical
c) Mechanical to electrical
d) Electrical to mechanical
Which of the following is responsible for the formation of rainbows?
a) Reflection of light
b) Refraction of light
c) Scattering of light
d) Diffraction of light