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Answer: The wavelength of the x-ray wave is 
Explanation:
To calculate the wavelength of light, we use the equation:

where,
= wavelength of the light = ?
c = speed of x-ray= 
= frequency of x-ray =

Putting in the values:

Thus the wavelength of the x-ray wave is 
Answer:
Their positive charge is located in the small nucleus
Explanation:
Ernest Rutherford performed the gold foil experiment in 1911 where he used alpha particles generated from a radioactive source to bombard a thin gold foil.
In his experiment, he observed that the bulk of the alpha particles passed through the gold foil, just a tiny fraction was deflected back. To explain his findings, Rutherford proposed that an atom is made of positively charged centre where nearly all the mass is concentrated called nucleus. Surrounding the nucleus is a large space containing electrons.
Answer:
salt is dull and brittle and conducts electricity when it has been dissolved into water, which it does quite easily.
Explanation:
transparent and colourless in crystalline form- rather like ice.