Answer:
Lithium oxide, Li₂O.
Explanation:
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In this case, according to the given amounts, it is possible to write down the chemical reaction as shown below:

Which means that the metallic oxide has the following formula: M₂O. Next, we can set up the following proportional factors according to the chemical reaction:

Thus, we perform the operations in order to obtain:

So we solve for x as shown below:

Whose molar mass corresponds to lithium, and therefore, the metallic oxide is lithium oxide, Li₂O.
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Mass number minus atomic number equals neutrons.
234-92=142
Answer:
The temperature associated with this radiation is 0.014K.
Explanation:
If we assume that the astronomical object behaves as a black body, the relation between its <em>wavelength</em> and <em>temperature</em> is given by Wien's displacement law.

where,
λmax is the wavelength at the peak of emission
b is Wien's displacement constant (2.89×10⁻³ m⋅K)
T is the absolute temperature
For a wavelength of 21 cm,

J. J. Thomson, who discovered the electron in 1897, proposed the plum pudding model of the atom in 1904 before the discovery of the atomic nucleus in order to include the electron in the atomic model. In Thomson's model, the atom is composed of electrons (which Thomson still called “corpuscles,” though G. J.