Answer:
Explanation:
Dalton's atomic theory proposed that all matter was composed of atoms, indivisible and indestructible building blocks. While all atoms of an element were identical, different elements had atoms of differing size and mass.
In 1897, J.J. Thomson discovered the electron by experimenting with a Crookes, or cathode ray, tube. He demonstrated that cathode rays were negatively charged. In addition, he also studied positively charged particles in neon gas.
Rutherford overturned Thomson's model in 1911 with his well-known gold foil experiment in which he demonstrated that the atom has a tiny and heavy nucleus. Rutherford designed an experiment to use the alpha particles emitted by a radioactive element as probes to the unseen world of atomic structure.
The Bohr model shows the atom as a small, positively charged nucleus surrounded by orbiting electrons. Bohr was the first to discover that electrons travel in separate orbits around the nucleus and that the number of electrons in the outer orbit determines the properties of an element.
Answer:
The correct option is B
Explanation:
One of the claims of John Dalton's atomic theory is that atom is the smallest unit of matter (which suggests that there are no particles smaller than an atom in any matter). This claim has been disproved by the modern atomic theory which established that there are particles smaller than atom (called subatomic particles). These particles are electrons, protons and neutrons.
One of the modern atomic theory was by Neils Bohr, who proposed that <u>electrons move in circular orbits around the central nucleus</u>. Thus, the electrons of iron can also be said to be present in a region of space (circular path) around the nucleus. This proves that option B is the correct option as John Dalton's theory did not even recognize the electron(s) nor the nucleus.
Answer:
Certain types of atoms are "radioactive," meaning that they will eventually decay, or "break down" into a different type of atom. In this activity, you will simulate radioactive decay by flipping coins. Coins that land tails-up "decay," and coins that land heads-up remain the same.
Explanation:
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Answer:
Acid: HCl(aq), conjugate base: Cl⁻(aq)
Base: CO₃⁻²(aq), conjugate acid: HCO₃⁻(aq)
The rewrite reaction is shown below.
Explanation:
The acid compound is the one that loses an H⁺, and the compound formed when it happens is its conjugate base. The base compound is the acceptor of H⁺, and its conjugate acid is the compound formed (Brosted-Lowry theory).
So, the acid-base pairs are:
Acid: HCl(aq), conjugate base: Cl⁻(aq)
Base: CO₃⁻²(aq), conjugate acid: HCO₃⁻(aq)
The TUMS® is an antacid, so it intends to reduce the concentration of the strong acid HCl. So, the forward reaction is favored. It can be represented with the forward arrow larger than the reversible arrow, as shown in the image below.
