Explanation:
Given that,
Mass of metal cube, m = 20 g
Volume of cube, V =5 mL
We need to find the density of the cube. Mass per unit volume equals density.

So, the density of the cube is 4 g/ml.
We know that the density of Aluminium is 4 g/mL.
So, the cube is not Aluminium cube.
Answer:
The difference in mass between 3.01×10^24 atoms of gold and a gold bar with the dimensions 6.00 cm X 4.25 cm X 2.00 cm is :
<u>Difference</u> <u>in mass</u> =<u> 985.32 - 984.5 = 0.82 g</u>
Explanation:
<u>Part I :</u>

n = 4.9983
n = 4.99 moles
(Note : You can also take n = 5 mole )
Molar mass of gold = 196.96 g/mole
This means, 1 mole of gold(Au) contain = 196.96 grams
So, 4.99 moles of gold contain =
g
4.99 moles of gold contain = 984.8 g
Mass of
atoms of gold = 984.5 g
<u>Part II :</u>
Density of Gold = 
Volume of the cuboid = 
Volume of the gold bar =
Volume of the gold bar = 51
Using formula,

Mass = 985.32 g
So, A gold bar with the dimensions 6.00 cm X 4.25 cm X 2.00 cm has mass of <u>985.32 g</u>
<u>Difference</u> <u>in mass</u> =<u> 985.32 - 984.5 = 0.82 g</u>
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:
Explanation:
At three-quarters of a teaspoon of baking soda, the cookie's texture becomes fragile like that of a soda cracker, with a deeply roasted flavor that distracts from the ginger.
The answer would be uranium and thorium. When an alpha ejects a particle, it will create a new atom. So, when uranium ejects an alpha particle, it will produce thorium. They call this process as the alpha decay. Alpha decay often happens on atoms that are abundant nuclei such as uranium, radium, and thorium.