<span> First you need to know how many isotopes there are of silicon, and its average atomic units (look at periodic table). Then make up a system of equations to solve for it. Theres 3 stable silicon isotopes (28, 29, 30) so you will need to have 3 equations. You must be given the percent abundance of at least one of the isotopes to solve because here I can only see 2 equations (numbered down below) set x = percent abundance of si-28 y = percent abundance of si-29 z = percent abundance of si-30 since all of silicon atoms account for 100% of all silicon: x + y + z = 100% = 1 therefore: 1) x = 1 - y - z You also have 2) 28x + 29y + 30z = average atomic mass you can substitute x so that equation becomes: 28 (1 - y - z) + 29y + 30z = average atomic mass See how you have 2 variables here? You cant go on until you know the value of one isotope already or you have given a clue which you can derive the third equation</span>
Answer:
Explanation:
It is malleable, ductile, and a good conductor of electricity and heat.
Im pretty sure a cinder-cone volcano
Scientists repeat experiments for reliability. Experiments have to be repeated, since performing an experiment only once, does not prove a scientists theory on the experiment, which they develop by performing the experiment. And then performing the experiment again or even many times to prove or disapprove their theories. Btw, before an experiment begins, the scientist will make a hypothesis of what they believe will happen. If proven correctly, they would then use those results they record throughout the experiment, from beginning to end to prove whether or not their hypothesis are correct or incorrect. Click to let others know, how helpful is it
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So that they can prove the other scientists views wrong and develop a new theory in which there is more sense and credibility.
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BASICALLY, I THINK THE ANSWER IS 1 OR 2 OR
C magnetic repulsion, forgive me if I’m wrong