Answer:
A. Atoms are the smallest unit of an element.
Explanation:
The correct statement from the given choices is that atoms are the smallest unit of an element.
Atoms are the smallest particles that takes part in chemical reactions and they are made up of protons, neutrons and electrons.
- Elements are distinct substances that cannot be split up into simpler substances.
- They are made up of only one kind of atoms.
- Elements are not changed into atoms by chemical reactions.
- In chemical reactions, atoms simply recombine.
Answer:
Option (B)
Explanation:
A lift chart usually refers to a graphical representation that is mainly used in order to improve the drawbacks of a mining model by making a comparison with any random guess, and also helps in determining the changes that occur in terms of lift scores.
It describes the binary classification of the problems associated with the mining activity. This type of chart is commonly used to differentiate the lift scores for a variety of models, and picking the best one out of all.
Thus, the correct answer is option (B).
This would prove that gold is an <em>element</em>. No matter how far down you
examine it, you never find any particles of anything except gold.
An example of a different case is salt.
-- Imagine you had a block of salt and decided to cut it in half.
-- If you repeated this process, then eventually, at some point, you'd have
a tiny particle of salt in front of you, just like before. BUT ...
-- Just as you were getting ready to cut this one in half, you'd notice that this
particle of salt is different. It's one atom of sodium stuck to one atom of chlorine,
and if you cut it in half, you would not have ANY salt. <span />
This would prove that salt is a <em><u>compound</u></em>, made of atoms of two or more elements.
Answer:
2 Mg(s) + O2(g) → 2 MgO(s)
As magnesium (Mg) has a valency of +2, and oxygen (O) has a valency of -2, the ratio would be 1:1, and magnesium oxide would be represented as MgO. It is insoluble in water, hence it has the subscript as a solid, represented by (s). In order to use up the diatomic oxygen (O2), there needs to be two moles of magnesium (2Mg) on the reactant side. This would produce 2 moles of MgO on the product side.
Explanation:
