Thank you for your time.

1) In an experiment, some seeds were buried under some soil (depth of soil is covering the seeds is shallow).Can the seeds germinate? What happens when they are buried too deeply?

2) Some seeds were put into a beaker of pond water covered with a layer of oil. Can the seeds germinate?

3) When the water boils at 100 degree C, bubbles can be seen. What is inside these bubbles? (1) Air (2) Steam (3) Water (4) Water vapour

Wow! you post so many questions! saw them all over this site. u must be a fan of onsponge? look so scary... are they qns from schools? ok i try to help but only because i recently saw some material on seed germination from my son's school.

Seeds actually do not need sunlight to germinate just water, air and right temperature. So in the first qn, the seeds will germinate but we can only assume that the soil is not hard and dry. In fact doesn't that explains why when we need to grow a plant, we try to lossen the soil, place the seed in then water it regularly? If buried too deeply - then it depends on how deep?

As for qn2, pond water has oxygen and if not cold in temperature, the seed should germinate if based on the concept. The layer oil is often used to trick students thinking that sunlight is needed for germination.

By the way, are these qns from schools or what, quite vague. i thought normally they should be more specific else how the kids know?

Q3) When water boils at 100 degree C,bubbles can be seen what is inside these bubbles?

Tian, suggest you go do this experiment apart from posting the Q to better experience the answer yourself. Boil a pot of water, sit and observe all the things that actually happen during boiling that we all missed out in our daily interactions with water! have a thermometer by.

As you sit and watch the water gets to boil, get a thermometer to confirm that indeed at 80 degree C, small bubbles will already start to appear at the side and bottom of your pot/beaker. This is the dissolved air/gas that is held in solution by the water.

As you continue to heat the water, it causes the molecules of water to move faster and faster. Once they moved fast enough, they break away from the other molecules and change from liquid to gaseous state. The molecules of water then turn into the tiny bubbles of water vapor. When the bubble gets large enough, it breaks free and begins to rise. If you are still watching the action going on in the pot, you will see an amazing thing -the bubble vanishes before it reaches the top of the water! Why, go figure it out as i would tell my kids

Thanks Bing. Doing school / home experiments is clearly a great way to learn. Please ensure when doing them at home that you have your parent’s supervision and in this particular case, you have a thermometer that can withstand high temperatures as some may crack at boiling temperatures.

c