School Certificate Science MARATHON (1 Viewer)

[HiHaii]

Which elements make up zinc acetate?
Given:
Zn(CH3COO)2.2H2O
Harmful if swallowed
Avoid contact with eyes
Irritating to respiratory system

The answer is: zinc, carbon, hydrogen and oxygen.
Im not sure why it is that answer. ZnCHO ?

I'm also not very sure the life cycle of a star.
Is my explanation right?

nebula--->protostar--->red giant--->white dwarf--->red supergiant--->supernova--->neutron star--->black hole

 

[Hayzazz]

1. Its just asking for the names of the elements, not the number of them, so zinc, carbon, hydrogen and oxygen is correct.

2. Your explanation of the life cycle of the star is wrong.
I think its: nebula > protostar > main sequence star > red giant > nova > white dwarf
or it can be: nebula > protostar > main sequence star > red supergiant > supernova > black hole

 

[nehmch1]

yeahh that sounds ritee

 

[lpodnano]

GOOD LUCK FELLOW '11ers.

Good luck in your science test. But you are all a bunch of geniuses and probably don't need it like I do.

 

[Entity]

I dont see another question up there, so ima put my own one up.

What is a Red Shift?

 

[Riot09]

outline the scientific method using an example(science experiment) of youre choice.include:variables,fair test,repetition,accuaracy and reliability.

 

[salih08]

I dont see another question up there, so ima put my own one up.

What is a Red Shift?

The expansion of galaxies (?)

 

[salih08]

outline the scientific method using an example(science experiment) of youre choice.include:variables,fair test,repetition,accuaracy and reliability.

cant be bothered writing this but there is some good info on writing a method here: Science SKILLS answer. | Facebook

 

[HiHaii]

1. Its just asking for the names of the elements, not the number of them, so zinc, carbon, hydrogen and oxygen is correct.

2. Your explanation of the life cycle of the star is wrong.
I think its: nebula > protostar > main sequence star > red giant > nova > white dwarf
or it can be: nebula > protostar > main sequence star > red supergiant > supernova > black hole

hmm it doesn't seem right you left out neutron star

 

[silence--]

the life cycle of a star depends on its solar mass.

the first cycle zazz describes is the cycle stars like our sun go through. the second is for stars that are about 10x as bigger. only stars that are around 50x bigger than the sun become neutron stars. this is all iirc

idk if all this is sc material though, the first cycle there is probably all you need to know

 

[Hayzazz]

the life cycle of a star depends on its solar mass.

the first cycle zazz describes is the cycle stars like our sun go through. the second is for stars that are about 10x as bigger. only stars that are around 50x bigger than the sun become neutron stars. this is all iirc

idk if all this is sc material though, the first cycle there is probably all you need to know

Shouldn't it be the other way round? Like 10x bigger forms a neutron star and 50x bigger forms a black hole?

I'm not too sure about this topic, but I thought that only the biggest stars could form black holes.

 

[silence--]

oh wait, yeah that's right. my bad heh.

 

[Mudkip94]

My Question: Name the bases in DNA.

 

[mizz_a]

My Question: Name the bases in DNA.

adenine with thymine
cytosine with guanine

Qns: Identify properties that make some natural resources economically important and describe the uses

 

[Mudkip94]

Qns: Identify properties that make some natural resources economically important and describe the uses

Corn, it's a basic crop and feeds lots of peeps and is also used to make fuel (ethanol).

My Question: Outline light absorption.

 

[zxreth]

when something absorbs light or heat.

QUESTION: what is the general name given to chemicals that change colour in acids or bases?

 

[mizz_a]

absorption is the process in which the incident energy is absorped without reflection or transmission.
(my teacher gave me this ans...if anyone has a better ans, i'd like to know)

Qns: Evaluate the usefulness of models in understanding scientific concepts

 

[mizz_a]

when something absorbs light or heat.

QUESTION: what is the general name given to chemicals that change colour in acids or bases?

oops
general name is: indicators

 

[Forev3r]

models arre significant as they give us an understanding of the scientific process?? they are able to be test and remodelled if it was unable to evaluate it?? idkkk


Q what is the difference between nuclear fission and fusion

 

[Clank_]

Fission is the splitting of heavier nuclei (Uranium) by nuclear bombardment, releasing energy.
Fusion is the joining of lighter nuclei (Hydrogen) to form heavier elements (Helium), thus release energy.

Question: What is an index fossil, and how can they contribute to our knowledge of evolution ?