3. It makes china rose into a dark pink/magenta).
4. It does not give any colour change with litmus paper.
S. It is sticky to touch.
Linkee process and events with causes.
Give reasons for the following statements.
1. Penguins can easily live in the polar regions.
(2
2. The winds flow from the sea towards the land in summer.
3. Place a crumpled piece of paper on the mouth of an empty bottle and it comes outside (1
when you blow air inside the bottle.
Applies learnt scientific concepts in everyday life.
Answer the following questions.
1. What steps will you take to prevent rusting in your cycle?
2. How will you help your neighbours when cyclone approaches towards your
village/town?
Explains the process and events,
Explain the following process/events.
Answers
Answer:
3.China rose is a natural indicator which changes colour to determine the nature of an acid or a base. Lime juice is highly acidic with a pH of 2.5. ... Hence, when treated with lime juice it turns into magenta colour.
4.Water as it has a 7 pH level So it is neutral and it will not Change the Colour.
5.Lemon-Juice
(II)Question
1.Statement 1 - Penguins can easily live in the polar region because they have maintain high body temperatures to remain active. The thick skin helps to maintain warm in cold temperature. The feathers are tightly attached and overlap to one another, it provide waterproofing and warmth.
2.During the day, the sun heats up both the ocean surface and the land. ... The wind will blow from the higher pressure over the water to lower pressure over the land causing the sea breeze. The sea breeze strength will vary depending on the temperature difference between the land and the ocean. At night, the roles reverse.
3.As you blow into the mouth of the bottle the air is moving fastest - so is at the lowest pressure. Inside the bottle, the air is moving more slowly - so a higher pressure. As the pressure is higher inside the bottle than in the mouth this pushes the paper out!
Answer the following Questions:
1.Preventing corrosion
Removing substances that cause rusting
Rusting can be prevented by keeping oxygen or water away from the iron or steel:
oxygen can be excluded by storing the metal in an atmosphere of unreactive nitrogen or argon
water can be excluded by storing the metal with a desiccant such as calcium chloride
A desiccant is a substance that absorbs water vapour, so it keeps the metal dry.
Physical barriers to oxygen and water
Many methods of rust prevention rely on creating a physical barrier to oxygen and water. These include:
•Painting
•Oiling and greasing
•Coating with plastic
Different methods are used depending on the situation.
2.I will help my neighbours in case cyclone approaches my village/town by the following ways: (i) I will help in, shifting their household articles, domestic animals, etc to safe place. (ii) I will provide phone numbers of all emergency services like police, fire brigade and medical centres.