WorksheetsPlumbing Science lvl 2 mock exam
Total questions: 56
Worksheet time: 28mins
What is the chemical formula for water?
H2O
CO2
O2
H2SO4
Why is it rare to find pure water?
Water is a weak solvent.
Water is a very powerful solvent.
Water is a solid at room temperature.
Water is a gas at room temperature.
What can water do given enough time?
Freeze, melt, evaporate
Erode, corrode, absorb
Boil, condense, solidify
Expand, contract, dissolve
What happens to water when it is heated to temperatures up to 100°C?
It contracts by 4%
It expands by up to 4%
It turns into ice
It remains unchanged
When water exceeds 100°C, what transformation occurs?
It turns into ice
It evaporates and contracts
It turns to steam and expands
It remains liquid
By how much can water expand when it turns to steam at temperatures exceeding 100°C?
100 times its original volume
500 times its original volume
1,600 times its original volume
2,000 times its original volume
What is the standard unit for measuring temperature when considering the effect of heat on a space or object?
Fahrenheit
Kelvin
Celsius
Rankine
How is an increase in temperature often measured?
Fahrenheit
Kelvin
Celsius
Rankine
What is the equivalent of 0 Kelvin in Celsius?
-273°C
0°C
273°C
100°C
Which of the following statements is true about Celsius and Kelvin increments?
Celsius increments are larger
Kelvin increments are larger
Celsius and Kelvin increments are the same
Kelvin increments are smaller
What happens to molecular bonds as water is heated?
They strengthen and molecules move closer.
They weaken and molecules become more active and further apart.
They remain unchanged and molecules stay in place.
They disappear and molecules stop moving.
How are ice molecules arranged compared to steam molecules?
Ice molecules are spread further apart than steam molecules.
Ice molecules are tightly packed together, while steam molecules are spread further apart.
Ice molecules are more active than steam molecules.
Ice molecules are in constant motion, unlike steam molecules.
What is the boiling point of water at sea level?
0°C
4°C
100°C
273°C
By what percentage does water expand from 4°C to 99°C?
2%
4%
6%
10%
How many times does steam expand compared to water?
100 times
500 times
1,000 times
1,600 times
At what temperature does ice expand by 10%?
0°C or 273°K
4°C
100°C
99°C
What happens to the boiling point of water when the pressure is increased?
It decreases
It remains the same
It increases
It fluctuates
At what pressure does the boiling point of water significantly increase, as shown in the document?
1 bar
5 bar
10 bar
0.1 bar
What is sensible heat?
Heat that changes the state of water
Heat that raises the temperature of water without changing its state
Heat that cools water
Heat that evaporates water
What happens when latent heat is applied to water?
The water temperature rises without changing state
The water cools down
The water changes from liquid to steam
The water freezes
Which type of heat is required to keep water boiling?
Sensible heat
Latent heat
Radiant heat
Conductive heat
What is sensible heat?
Heat that changes the temperature of a substance without changing its state
Heat that changes the state of a substance without changing its temperature
Heat that is lost to the environment
Heat that is absorbed by a solid
What happens when latent heat is applied to water?
The water temperature rises without a change in state
The water changes from liquid to gas
The water freezes
The water remains in the same state
What type of heat is required to keep water boiling?
Sensible heat
Latent heat
Radiant heat
Conductive heat
What characteristic does water develop due to its ability to erode, corrode, and absorb dissolve?
Hardness or softness
Density or viscosity
Color or clarity
Temperature or pressure
What is another characteristic of water related to its ability to erode and corrode?
Acid or alkaline
Hot or cold
Light or heavy
Fast or slow
What is the term used to describe the hardness in water that affects soap lathering?
Soap enhancing factor
Soap destroying factor
Soap neutralizing factor
Soap balancing factor
What type of hardness in water contains calcium carbonates?
Permanent hardness
Temporary hardness
Total hardness
Neutral hardness
How can temporary hardness in water be removed?
By adding salt
By filtering
By heating the water above 65°C
By using a chemical softener
What does permanent hardness in water contain?
Calcium carbonates
Calcium sulphates
Magnesium chlorides
Sodium bicarbonates
Which method is used to remove permanent hardness in water?
Filtration
Boiling
Base exchange method
Distillation
What happens to temporary hard water when it is heated to 65°C and above?
It becomes very soft water.
It forms limescale (calcium carbonate).
It turns into permanent hard water.
It dissolves completely.
What is a consequence of limescale formation in appliances?
Improved efficiency of appliances.
No effect on appliances.
Problems for appliances and reduced efficiency.
Increased water flow in appliances.
What does the pH scale measure in water?
Temperature
Potential hydrogen
Salinity
Hardness
What pH value is considered neutral for water?
5
6
7
8
What type of water is likely to cause acidic corrosion and pitting?
Neutral water
Alkaline water
Acidic water
Distilled water
What is a potential effect of alkaline water?
Corrosion
Pitting
Limescale
Rust
What is the primary purpose of fitting a water softener?
To remove hard water and prevent scale, scum, and tide marks.
To increase water pressure.
To add minerals to the water.
To filter out bacteria and viruses.
What does the resin in a water softener hold?
Calcium and magnesium.
Sodium and potassium.
Iron and copper.
Chlorine and fluoride.
What solution is used to back-wash the unit in a water softener?
Brine solution (salt or sodium chloride).
Vinegar solution.
Baking soda solution.
Lemon juice solution.
What is the primary function of polyphosphate chemicals in water treatment?
Soften the water
Stabilize salts to prevent scale
Increase water temperature
Remove impurities
What do salt crystals tend to form when they bind together?
Soft water
Hard scale
Liquid solution
Gas bubbles
Where are polyphosphate chemicals commonly used?
In swimming pools
In combination boilers
In air conditioning units
In refrigerators
What is the purpose of a magnetic scale inhibitor in plumbing?
To heat the water
To filter out impurities
To break down salt crystals
To increase water pressure
How does a magnetic scale inhibitor alter the water?
It changes the color of the water
It alters the physical nature of the water
It increases the water's temperature
It adds minerals to the water
What does an electrical scale inhibitor use to produce low level radio waves?
Magnetic field
Electric current
Chemical reaction
Heat energy
What materials are used in a galvanic cell scale inhibitor to form an electron flow?
Zinc and copper
Iron and nickel
Silver and gold
Aluminum and tin
In a galvanic cell scale inhibitor, which metal acts as the anode that will break down?
Copper
Zinc
Iron
Silver
What is the term for water's ability to dissolve lead?
Cuprosolvent
Adhesiveness
Plumbosolvent
Cohesiveness
What property of water describes its aggressiveness towards copper?
Plumbosolvent
Cuprosolvent
Adhesiveness
Cohesiveness
What is the term for water's ability to cling to solids?
Cohesiveness
Cuprosolvent
Adhesiveness
Plumbosolvent
What is the term for water's ability to cling to itself?
Adhesiveness
Cohesiveness
Plumbosolvent
Cuprosolvent
What property allows a glass to be filled above the rim?
Adhesiveness
Cuprosolvent
Cohesiveness
Plumbosolvent
What is one problem plumbers face due to capillary action of water?
Water can be drawn up underneath the lead weathering on tiles.
Water can evaporate quickly from surfaces.
Water can freeze inside pipes.
Water can cause metal to rust.
Which of the following is a result of capillary action in plumbing?
Water can be drawn up between lead weathering surfaces.
Water can cause pipes to expand.
Water can increase the temperature of surfaces.
Water can create electrical conductivity.
What is a potential issue caused by the loss of a trap seal (S trap) under an appliance?
It can lead to unpleasant odors.
It can cause electrical shorts.
It can result in increased water pressure.
It can lead to pipe corrosion.
