The answer is: D.unstable nuclei emitting high-energy particles as they formed more stable compositions.
Those high-energy particles are alpha particles
, beta particles
, gamma radiation.
For example, the decay chain of ²³⁸U is called the uranium series.
Decay start with U-238 and ends with Pb-206. There are several alpha and beta minus decays.
Antoine Henri Becquerel (1852 – 1908) was a French physicist and the first person to discover evidence of radioactivity.
Becquerel wrapped fluorescing crystal (uranium salt potassium uranyl sulfate) in a cloth, along with the photographic plate and a copper Maltese cross.
Several days later, he discovered that a image of the cross appeared on the plate.
The uranium salt was emitting radiation.
Because of this discovery, Becquerel won a Nobel Prize for Physics in 1903, which he shared with Marie Curie and Pierre Curie.
Answer:
Atomic emission spectrum came out by a series of colored lines
Explanation:
When electricity is passing through an element or when it is viewing through a prism, a unique spectra of light emitted by an element is called atomic emission spectra. They are acting as an element of finger print because they are unique. When we are seeing a set of colored lines or a black background , it is an emission spectrum. If we are watching black lines on a colored background it is absorption spectrum. In electromagnetic spectrum the visible portion are the colors.
In nucleus electrons can exist in some areas are known as shells. Shell corresponds an energy level that is designed by a quantum number n. The lowest energy level electrons are close to the nucleus.
An atom is shone by light, its electrons absorbs photons and it gain energy, and jump to higher level.
Answer:
The formula for calculating pH is pH=−log[H_3O+ ]
pH is the negative logarithm (to base 10) of hydronium ion concentration
The pH Formula can also be expressed as
PH= - log[H+ ]
Answer:
=8 atoms
Explanation:
In (NH4)2C2O4 there are four moles of Hydrogen in the compound (NH4), but there two molecules of (NH4) in this compound. That's what the 2 in (NH4)2 means, so multiply 4 x 2 = 8.
Hope this helps (:
