The condition at which the entropy of a pure solid will be zero is<span> when a substance is at absolute zero. Absolute zero is </span><span>the lowest temperature that is theoretically possible, at which the motion of particles which constitutes heat would be minimal. It is zero on the Kelvin scale, equivalent to −273.15°C.</span>
Answer:
2s2 2p5
Rb < Sr< Sn< Te<I
Explanation:
Electron affinity is the ability of an atom to accept electrons to form negative ions.
Electron affinity is a periodic trend that decreases down the group but increases across the period.
This accounts for the trends observed in the answer. The atom having the electronic configuration, 2s2 2p5 must be a halogen and it exhibits the highest value of electron affinity.
Also, since electron affinity increases across the period, the electron affinities of the elements increases. Therefore, the arrangement of atoms as shown in the answer depends on increasing electron affinity.
Answer: 700 has one significant figure which is 7.
Explanation: These are some rules for significant figures
•All non-zero digits are significant: 1,2,3,4,5,6,7,8,9
•Zero between non-zero digits are significant: They are three significant figures in 203.
•Leading zeros are not significant: There are two significant figures in 0.56.
•Trailing zero to the right of decimal are significant. There are four significant figures in 62.00
•Trailing zeros in a whole number with the decimal shown are significant: This makes "700." three significant figures.
•Trailing zeros in a whole number with no decimal shown are not significant: This makes 700 one significant figure.
The correct answers are:
1. B. Mg loses two electrons.
When Mg and Br combine, 2 atoms of Br attaches itself to
Mg. The chemical reaction is:
Mg + Br ---> MgBr2
Since Br is more electronegative than Mg, then Mg loses
an electron per Br therefore losing 2 electrons.
2. D. An atom that gains electrons must be attracted to an atom
that loses electrons.
An ionic bond is formed when one molecule is more
electronegative than the other molecule which results in gaining and losing of
electrons. The more electronegative molecule gains electron while the less
electronegative loses electron.
