Answer:
The correct answer is C. element
Explanation:
The sample cannot be an element because an element - or <em>elemental substance</em> - cannot be decomposed into simpler substances. Thus, it cannot be composed by differents types of atoms. For example, an element is carbon (C).
As the sample contains <u>three types of atoms</u>, it can be a compound, a molecule or a mixture, because they can be composed by different types of atoms - of different chemical elements. For example, the sample could contain the element carbon (C) combined with other elements, for example oxygen (O) or hydrogen (H), amoing others.
Answer:
2.52 x 
J
Explanation:
The energy given off by the microwave can be determined by the application of Planck's energy formula:
E = hf
where: E is the required energy, h is Planck's constant (6.626 x 
Kg/s), and f is the frequency (3.8 x 
Hz).
So that;
E = 6.626 x x 3.8 x
= 2.51788 x
Therefore, the energy released by the wave is 2.52 x J.
Wanted to write more both there is a problem with the editor. Uranium is formed naturally in the crust of rocks and seawater. Plutonium does not occur in nature. It is found in the biosphere.
Answer:
In 1897, the British physicist J. J. Thomson (1856–1940) proved that atoms were not the most basic form of matter. He demonstrated that cathode rays could be deflected, or bent, by magnetic or electric fields, which indicated that cathode rays consist of charged particles (Figure 2.2.2 ). More important, by measuring the extent of the deflection of the cathode rays in magnetic or electric fields of various strengths, Thomson was able to calculate the mass-to-charge ratio of the particles. These particles were emitted by the negatively charged cathode and repelled by the negative terminal of an electric field. Because like charges repel each other and opposite charges attract, Thomson concluded that the particles had a net negative charge; these particles are now called electrons. Most relevant to the field of chemistry, Thomson found that the mass-to-charge ratio of cathode rays is independent of the nature of the metal electrodes or the gas, which suggested that electrons were fundamental components of all atoms.
Explanation:
