Last updated on April 24th, 2024 at 04:38 am
Maharashtra Board Class 4 EVS Water Safe for Drinking
If you are looking for solutions of Maharashtra Board Class 4 EVS Water Safe for Drinking then you are at the right place.
Answer the following questions.
Q: Name the substances used to make the solution called lemon sherbet.
A: The substances used to make the solution called lemon sherbet typically include lemon juice, sugar, water, and sometimes carbonated water or soda.
Q: Why is it that water that looks clean and transparent may not be fit for drinking?
A: Water that looks clean and transparent may not be fit for drinking because even though it may appear clean, it could still contain harmful microorganisms or dissolved impurities that are not visible to the naked eye. These impurities could pose health risks if ingested.
Q: When making a sherbet, what do we do to make sugar dissolve quickly?
A: To make sugar dissolve quickly when making a sherbet, we typically stir or agitate the mixture vigorously. This increases the surface area of the sugar particles in contact with the water, facilitating faster dissolution.
Q: Does oil float on water or sink in it?
A: Oil typically floats on water because it is less dense than water. Oil and water do not mix well due to differences in polarity and density, so oil forms a distinct layer on the surface of water.
Fill in the blanks.
- Substances like salt and sugar ……………….. after some time when added to water.[dissolve]
2. The mixture obtained on dissolving a substance in water is called a ………….. .[solution]
3. ORS is an example of ……………. solutions.[useful]
4. All micro-organisms are not useful. Some can cause …………. if they enter our body.[diseases]
5. Things that float in water are ………. than it and things that sink are………..than it.[lighter , heavier]
6. A substance called ……………… is swirled in muddy water to help clean the water.[alum]
True or false ?
- Alum powder does not dissolve in water.[False]
2. Micro-organisms cannot live in water. [False]
3. If muddy water remains still, a sediment is formed at its bottom.[True]
4. An eraser floats in water. [False]
5. Tea leaves can be separated from tea by filtration.[True]
Additional Que Ans
Q: What is the purpose of swirling alum in muddy water?
A: Swirling alum in muddy water helps the soil particles to settle down, aiding in the cleaning process.
Q: Why is it necessary to boil water even after it has been cleaned by settling and filtration?
A: Boiling water is necessary to kill any remaining microorganisms that may be present, ensuring it is safe for drinking.
Q: What precaution should be taken if water has a foul smell or color?
A: Water with a foul smell or color should be avoided as it may indicate the presence of contaminants that could make us ill.
Q: Why do some substances dissolve in water while others do not?
A: Substances dissolve in water if they are soluble, meaning their molecules can mix evenly with the water molecules. Other substances do not dissolve if they are insoluble, meaning their molecules do not mix with water.
Q: What is the significance of microorganisms in our lives?
A: Microorganisms have great importance as they play various roles, such as converting milk into yogurt. However, some microorganisms can cause diseases when they enter our bodies.
Q: What is the process called when heavier particles settle to the bottom of still water?
A: The process is called settling.
Q: How can you separate tea leaves from tea?
A: Tea leaves can be separated from tea by filtration.
Q: Why do some substances float on water while others sink?
A: Substances that are less dense than water float, while those that are denser sink.
Q: What is the purpose of ORS (Oral Rehydration Solution)?
A: ORS is used to rehydrate individuals who are experiencing loose motions or dehydration by replenishing lost electrolytes.
Q: Why is it important to obtain safe drinking water?
A: Safe drinking water is essential to prevent illnesses caused by harmful microorganisms or contaminants present in water.
Multiple choice questions from the chapter
- A) What substances are commonly used to make lemon sherbet?
- A) Salt and sugar
- B) Lemon juice and oil
- C) Lemon juice, sugar, and water
- D) Milk and honey
Answer: C) Lemon juice, sugar, and water
- B) Why may water that looks clean not be fit for drinking?
- A) It is too cold
- B) It contains harmful microorganisms
- C) It has a transparent appearance
- D) It has a pleasant smell
Answer: B) It contains harmful microorganisms
- C) How can sugar dissolve quickly when making sherbet?
- A) Boiling the mixture
- B) Freezing the mixture
- C) Stirring or shaking the mixture
- D) Adding more sugar
Answer: C) Stirring or shaking the mixture
- D) What happens to oil when placed in water?
- A) It sinks
- B) It floats
- C) It dissolves
- D) It evaporates
Answer: B) It floats
- E) What is added to muddy water to help clean it?
- A) Sugar
- B) Salt
- C) Alum
- D) Lemon juice
Answer: C) Alum
- F) What does ORS stand for?
- A) Oxygen Replenishment System
- B) Oral Rehydration Solution
- C) Organic Residue Separator
- D) Oxygenated Respiratory System
Answer: B) Oral Rehydration Solution
