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A sample of the ore haematite contains 70% iron oxide. Calculate the amount of iron oxide in 2000 tonnes of haematite.

2000 tonnes H0.7 x 2000 tonnes = mass of iron oxide = 1400 tonnes
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Answered by Daisy O. • Chemistry tutor
4331 Views

Describe an experiment to determine the spring constant of a spring? Your answer should include any causes of inaccuracy.

A clamp and stand should be used to hold the spring in place. Ensure its parallel to the stand using a ruler, this reduces the effect of random parralax error when measuring extension.Masses should be attach...
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Answered by Andrew R. • Physics tutor
13472 Views

Explain why the nuclear model of the atom replaced the plum pudding model of the atom?

Rutherford performs the alpha particle scattering experiment. Alpha particles incident on a gold foil in a vaccum are scattered by a range of angles, due to the electrostatic repulsion between the positively...
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Answered by Andrew R. • Physics tutor
8355 Views

How do you conjugate the verbs Ser and Estar and when do you use them?

Ser and Estar are vital verbs for Spanish, so it is key to get them nailed and remember the conjugations. SER goes as SOY, ERES, ES, SOMOS, SOIS y SON. ESTAR is conjugated like this: ESTOY, ESTÁS, ESTÁ, ESTA...
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Answered by Luis C. • Spanish tutor
2075 Views

How does the development of antibiotic resistance in bacteria provide evidence for evolution?

A population of bacteria will have lots of variation in characteristics due to mutations in the DNA that each bacteria contains. Some of those mutations may allow a bacteria to be resistant to an antibiotic ...
LB
Answered by Laurence B. • Biology tutor
3779 Views