How it looks. basically the thing that tells you how it change. for example if an ice cube was melted (heat), it only changed physically not chemically as the h20 molecules are still there. however lets say you burn woos— you cant get that would back. its ash now and it has changed chemically.
D protons. <span>the identity of an element is determined by the total number of protons present in the nucleus of an atom contained in that partial element.
._.</span>
Answer:
when electron emit the radiations it means it jumped to the lower energy level from higher energy level.
Explanation:
When electron jump into lower energy level from high energy level it loses the energy.
The process is called de-excitation.
Excitation:
When the energy is provided to the atom the electrons by absorbing the energy jump to the higher energy levels. This process is called excitation. The amount of energy absorbed by the electron is exactly equal to the energy difference of orbits.
De-excitation:
When the excited electron fall back to the lower energy levels the energy is released in the form of radiations. this energy is exactly equal to the energy difference between the orbits. The characteristics bright colors are due to the these emitted radiations. These emitted radiations can be seen if they are fall in the visible region of spectrum.
Answer:
18.33 ×10²³ atoms
Explanation:
Given data:
Molar mass of sulfuric acid = 98.1 g/mol
Mass of sulfuric acid = 75.0 g
Number of of oxygen atom present = ?
Solution:
Number of moles of sulfuric acid:
Number of moles = mass/molar mass
Number of moles = 75.0 g/ 98.1 g/mol
Number of moles =0.761 mol
one mole of sulfuric acid contain four mole of oxygen atom.
0.761 mol × 4 = 3.044 mol
1 mole = 6.022×10²³ atoms of oxygen
3.044 mol × 6.022×10²³ atoms of oxygen / 1mol
18.33 ×10²³ atoms
Answer:
The correct answer will be "4.60 g".
Explanation:
The given values are:
Volume of Butane = 7.96 mL
Density = 0.579 g/mL
As we know,
⇒ 
On putting the estimated values, we get
⇒ 
⇒ 