Q&A - PSLE Science

[Belle2011]

tianzhu:

a)The procedures are:


D) Put the leaf in boiling water for 20 seconds.
A) Soak the leaf in a boiling tube of warm alcohol.
C) Wash the leaves in a beaker of water.
B) Put a few drops of iodine on the leaf.

b)The green colour of chlorophyll will mask the result of the iodine test if iodine solution were to simply drop onto the leaf surface. Hence, the leaf needs to be decolourised i.e., the chlorophyll needs to be removed. --- decolours the leaf

c)The leaf surface is tough and may be impermeable to iodine solution. Boiling the leaf in hot water helps to soften it by killing the cells and breaking down the cell walls and cell membranes. This enables the green colouring to be extracted. --- kills the leaf

Best wishes

Thank-you, tianzhu.
I am surprised by the answers. But I have learnt much from you.

Cheers,
Belle.

[janet88]

tianzhu:

janet_lee88:

Other than the must-haves PSLE Science reference (Marshall Cavendish) and Science Ultimate (EPH), are there any assessment book which are of help in the preparation please ? Thanks.

Just like going to an economical rice stall where there are so many dishes, sometimes having too many choices is also a problem.

If I may add, past years papers from top schools is also a must have.

Best wishes

Thanks tianzhu. I agree with you, there are simply too many too titles for each subject, esp of late. Thus, a parent like me with son in P5 is at a loss.
Hubby quoted an example from HOD for Science after a briefing.
If there is a puddle of water on the floor, why would the student not see it after few hours ?
I said, 'the water has evaporated'. (WRONG).
The answer should be, the heat from the surrounding has gone to the puddle of water, as such the water has gained heat and evaporated. (Sorry if incomplete, but this was roughly what hubby told me).

[tianzhu]

Belle2011:

Thank-you, tianzhu.

I am surprised by the answers. But I have learnt much from you.

Cheers,
Belle.

Hi Belle

You're welcome.

But, be beware, my answers may not be always correct.

Best wishes

[chrisu]

Thanks Tianzu and Janet_Lee88. Glad that this Phases of Moon no longer in the syllabus. Remember when my son was in P6 then, hard time for him to understand it.

tianzhu:

chrisu:

Understand that the 2011 PSLE Science followed the 2008 Science syllabus; would like to know is the Phases of the Moon (especially calculating the dates of the phases of the moon) still in this year PSLE syllabus? Saw some science questions in \"Road to PSLE\" on Phases of the Moon in 2008.

Thank you.

Hi

The topic on Day and Night cycles is not in the new syllabus.

You may wish to confirm it with your kid's teacher.

Best wishes

http://www.moe.gov.sg/education/syllabuses/sciences/files/science-primary-2008.pdf

http://www.punggolpri.moe.edu.sg/cos/o.x?c=/wbn/pagetree&func=view&rid=15664

[janet88]

Hi chrisu,

Out of greed, I bought several assessment books from roadshows at $2 each...only to realize later that they were old syllabus
Anyway, I'm using some of the topics/notes inside.
Phases of Moon is not easy.

[tianzhu]

chrisu:

Thanks Tianzu and Janet_Lee88. Glad that this Phases of Moon no longer in the syllabus. Remember when my son was in P6 then, hard time for him to understand it.

Hi

You're welcome.

For many young lovers, the moon is more than a ‘moon”, it’s associated with romantic feelings when one takes a slow walk with our loved ones by the sea.

The moon changes all the time, half moon, crescent moon to full moon. It’s always the same moon, how we look at it is a reflection of our lives.

I am pretty sure the moon reminds many parents of their happier moments during their ‘paktor times”. The sweetest moments of their lives.

However, questions on phases of moon bring tears to PSLE students. For 12 years kids, I must say it’s not an easy topic to comprehend.

You ask whether the phases of the moon is included in PSLE Science.
The answer is no.

The happiness is real.
The joy is real

Just one thin line
to cancel the topic
is enough to make me smile.

Best wishes

[janet88]

tianzhu:

chrisu:

Thanks Tianzu and Janet_Lee88. Glad that this Phases of Moon no longer in the syllabus. Remember when my son was in P6 then, hard time for him to understand it.

Hi
You're welcome.

For many young lovers, the moon is more than a ‘moon”, it’s associated with romantic feelings when one takes a slow walk with our loved ones by the sea.

Yes, I would associate the MOON to the song 'the moon represents my heart' but asking me to study it is another issue.

[chrisu]

How I wish I could have the \"heart\" and \"energy\" of both Tianzhu and Janet_Lee88! My eldest son just completed his O level last year and now I've to start preparing my daughter for her PSLE... :?:


Kept lots of Science and Maths paper from my son's time and now it's like useless as the syllabus changed. Teaching Science to P6 or P5 is not an easy task and definitely a \"specialised\" teacher is required. My daughter's form teacher teaches her class English, Maths and Science. But I can see that the number of Science period is little compared to the other major subjects and the teacher don't seem to be progressing much.

The CA1 is starting this coming Thursday and it covers all topics since P3. I wonder how many students are able to remember all those topic covered as this year they have to stay back in sch twice a week till 4.30pm and 1 more day for CCA from 4.15pm to 5.30pm. 3 days out of a week came back feeling tired and she had no mood to revise her work.

I really don't expect her to do well for her CA1.

[janet88]

chrisu:

Kept lots of Science and Maths paper from my son's time and now it's like useless as the syllabus changed. Teaching Science to P6 or P5 is not an easy task and definitely a \"specialised\" teacher is required. My daughter's form teacher teaches her class English, Maths and Science. But I can see that the number of Science period is little compared to the other major subjects and the teacher don't seem to be progressing much.

The CA1 is starting this coming Thursday and it covers all topics since P3. I wonder how many students are able to remember all those topic covered.
I really don't expect her to do well for her CA1.

I dare not expect son to do well for CA1 either, especially since we don't know format. Now I try to squeeze in science topics from p3 (quite a lot) and lifecycles. Last year's CA1 was a killer. Hope to do few more OE comprehension with him.

[adellwong]

Hi, I'm new here. Would like some help from the members on this P5 water cycle question. I'm very out of touch with science and it's been an uphill task for me and my SIL coaching my niece for this subject. Your help is greatly appreciated


source: http://www.oldschool.com.sg
Primary 5 Science (2010) : Matter - Water (Free Response Q10)

Johnathan used the set-up below to show the water cycle. He later observed that there were droplets of water formed at the underside of the plastic sheet and at the inner sides of the beaker.


http://www.flickr.com/photos/59692876@N05/

What is the purpose of putting ice cubes on the plastic sheet?
DN (=Darling NIece) 's answer: To lower the temperature of the plastic sheet.

State the 4 major changes that have led to the water droplets being formed.
DN's answer: Hot water evaporates to form water vapour.
Plastic sheet loses heat to the ice.
Water vapour loses heat to the cooler part of beaker and plastic sheet
and condenses to form water droplets.

Is my niece's answer acceptable?