Answer:
(b) Both have the same number of valence electrons.
Step-by-step explanation:
We find the most striking chemical similarities between two Main Group elements when they are in the same Group of the Periodic Table.
Elements in the same Group have the same number of valence electrons.
(a) is <em>wrong</em>, because elements in the same group have <em>different masses</em>.
(c) is <em>wrong,</em> because atoms with the same number of protons belong to the s<em>ame element</em>.
(d) is wrong, because elements in the same Group must be in .
<em>different Periods.</em>
Answer:
c.
Explanation:
One of the main differences between an atom and an element is that an atom can be combined but an element cannot be combined. There are many combinations of atoms that make up different gases, liquids, and solids each with a unique makup. For example, water is made up of two hydrogen atoms and one oxygen atom (H20). Elements are made up of only the same type of atom. For example, the element Hydrogen can only contain hydrogen atoms, while the element Carbon can only contain carbon atoms.
Answer: Hydrochloric acid poses a various health risk
D. is the missing element.
Carlos <em>hasn’t done research</em> on what other scientists have observed and investigated on this topic. If he hasn’t done his literature research, he may just be repeating the experiments of other scientists working in the same area.
Options “A.”, “B.”, and “C.” are all part of the scientific method.
Answer:
The atoms are ranked in decreasing order as follows:
Fluorine ---4
Carbon ----3
Boron ------2
Beryllium --1
Explanation:
Effective nuclear charge (Zeff) is defined as the difference between the actual nuclear charge (the atomic number, Z) and the shielding constant (S).
It is calculated by finding the atomic number and electronic configuration, attributing a shielding value to each electron, adding all the shielding values and using the formula:
Z eff = Z - S
Effective nuclear charges:
An atom of carbon: 3.25
An atom of fluorine: 5.20
An atom of beryllium: 1.95
An atom of boron: 2.60