Answer is: (2) Energy is absorbed and a bond is broken.
This energy is called bond-dissociation energy.
Bond-dissociation energy is the measure of bond strength in a chemical bond.
Bond energy of bromine molecule (sigma bond) is energy needed for breaking up one molecule of bromine into two bromine atoms.
When two bromine atoms (Br) form molecule of bromine (Br₂), than energy is released and bond is formed.
(2) 2 (4) 10
Answer:
C. 3
Explanation:
If you look at aluminum (Al) in the Periodic Table of the Elements, you will see that its electron configuration is 2-8-3. The last number indicates the valence shell, which contains three electrons.
(2) substitution (4) polymerization
(2) A positively charged nucleus is surrounded by mostly empty space.
(3) A negatively charged nucleus is surrounded by positively charged particles.
(4) A negatively charged nucleus is surrounded by mostly empty space.
Answer is: 2) A positively charged nucleus is surrounded by mostly empty space.
Rutherford theorized that atoms have their charge concentrated in a very small nucleus.
This was famous Rutherford's Gold Foil Experiment: he bombarded thin foil of gold with positive alpha particles (helium atom particles, consist of two protons and two neutrons).
Rutherford observed the deflection of alpha particles on the photographic film and notice that most of alpha particles passed straight through foil.
That is different from Plum Pudding model, because it shows that most of the atom is empty space.
The conclusion about the structure of the atom as the result of the gold foil experiment is that a positively charged nucleus is surrounded by mostly empty space. The answer is number 2. Also, he concluded that an atom was not an empty space but rather, the electrons are scattered.
Answer:
Some elements are abbreviated with more than two letters such as the Ununtrium (Uut), Ununpentium (Uup), Ununseptum (Uus) and Ununoctio (Uuo).
Explanation:
Some elements have intuitive symbology, such as Chlorine (Cl), among others, which are represented by the first letters that make up the name. However, there are others who receive symbols that do not remember the name of the element, such as Lead (Pb). Regardless of the similarity between the names and the symbol of the elements, most of them have the symbol composed of one or two letters, except for the elements Ununtrium (Uut), Ununpentium (Uup), Ununseptum (Uus) and Ununoctio (Uuo).
(2) protons (4) positrons