Answer:
We know based on the charges of each ion and the fact that they must always sum to 0
Explanation:
Na only has one outer electon to give so it is always +1
Mg has two outer electrons so it always gets +2
Halogens have one "missing" electron in their outer shell so they get a -1
For NaCl (+1) + (-1) = 0
For MgI2 (+2) + 2(-1) = 0
Answer:
Overall, ethanol is considered to be better for the environment than petrol. Ethanol-fuelled vehicles produce lower carbon dioxide emissions, and the same or lower levels of hydrocarbon and oxides of nitrogen emissions.
Explanation:
Answer is: Velocity and spacing of particles is reduced and Volume of substance decreases relative to temperature decrease.
Charles' Law (The Temperature-Volume Law) - the volume of a given amount of gas held at constant pressure is directly proportional to the Kelvin temperature:
V₁/T₁ = V₂/T₂.
When temperature goes down, the volume also goes down.
Velocity is equivalent to a specification of its speed and direction of motion, it is a physical vector quantity. Less enegry (lower temperature), lower the velocity.
Answer:
False
Explanation:
Half life is the time period at which the concentration of the radioactive substance in decay reduced to half.
<u>Thus, if the hydrogen-3 has gone 2 half lives, it means that it has first reduced to its half and then again the half of what it was, i.e. 1/4</u>
Thus, after two successive half-lives, the concentration must be 1/4 of the initial concentration and hence, the statement is false.
<span>The smallest unit of an element that retains all the characteristics of that element is called an A. atom.
Atoms consist of protons, electrons, and neutrons, but they are particles and don't have the characteristics of the element which is why D is incorrect. B and C are not the smallest units - atoms are smaller than them.
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