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Chemistry Forums for Students => High School Chemistry Forum => Topic started by: chengtai on March 05, 2024, 01:45:24 PM

Title: I need help with Q&A
Post by: chengtai on March 05, 2024, 01:45:24 PM
I need further clarification on these two questions.

For the first question, "the mixtures composed of two or more elements are called"
I initially answered 'compounds,' but the teacher marked it wrong, stating that the correct term is 'alloys.' Could you explain the distinction between these terms in the context of mixtures composed of two or more elements?

I'm seeking clarification on the second question. 'another name for mobile electrons are"
I knew it was 'free electrons' but it was not a choice; therefore, I just guess.
But the teacher indicated 'mobile electrons' as the correct answer. This seems like a tricky question to me. Could you please explain the reasoning behind the teacher's choice?






Title: Re: I need help with Q&A
Post by: Hunter2 on March 05, 2024, 02:01:35 PM
The first question is also not clear. We speak from an alloy, if you have a mixture of different molten metals. But if you say element it could be also any other element .A mixture of about 78% nitrogen and 21% oxygen and 1% rest gases is called air.
The second questi8n is strange

You say for "another name for mobile electrons are" the teacher answered mobile electrons. What kind of answer is that.
Title: Re: I need help with Q&A
Post by: chengtai on March 08, 2024, 11:46:36 AM
Thank you. Welcome more comment/remark.
Title: Re: I need help with Q&A
Post by: Borek on March 08, 2024, 01:28:14 PM
There is not much to be added - both answers are either wrong or make no sense.

For a mixture to be called an alloy it has to contain at least one metal. No metal, no alloy. Questions doesn't mention this condition, so the "alloy" answer is incorrect, as there are plenty of two elements mixtures that are not alloys.

Answering "another name for mobile electrons" with "mobile electron" is incorrect, as it is not "another name", it is the same name. It is not even a trick question, it is plain wrong.
Title: Re: I need help with Q&A
Post by: Babcock_Hall on March 13, 2024, 11:05:04 AM
I typically use the word "compound" when the elements are combined in a fixed ratio.  To the best of my understanding alloys have variable proportions.