- Mass=m=750g=0.75kg
- Q=78.45\times 10^3J=78450J
- T_i=100°C
- T_f=?
- Specific heat capacity=c=4200J/kg°C
According to thermodynamics
Answer:
1.88 x 10²³molecules of H₂O
Explanation:
Given parameters:
Mass of H₂O = 5.609g
Unknown:
Number of molecules of H₂O = ?
Solution:
To solve this problem, we need to find the number of moles of given compound first.
Number of moles = 
Molar mass of H₂O = 2(1) + 16 = 18g/mol
Number of moles = 
= 0.31mole
From mole concept;
1 mole of a substance contains 6.02 x 10²³molecules
0.31 mole of H₂O will therefore contain 0.31 x 6.02 x 10²³molecules
= 1.88 x 10²³molecules of H₂O
Answer:
Covalent bond
Explanation:
A covalent bond is defined as the sharing of election pairs between atoms
Rutherford was one of the early scientists who worked on the atomic model. Before his discovery of the nucleus, the widely accepted theory was J.J Thomson's Plum Pudding Model. In this model, all the protons, electrons and neutrons are in the nucleus. But the electrons are more in number such that the electrons act as the 'pudding' and the proton and nucleus the 'plum'. This was Rutherford's hypothesis in his gold foil experiment. In order to test the Plum Pudding model, he hypothesized that when a beam of light is aimed at the atom, it would not diffract because the charges in the nucleus are well-distributed. However, his experiment disproved Thomson's model. Some light indeed passed through but a few was diffracted back to the source. He concluded that this was because there is a dense mass inside the atom called nucleus. Thus, from there on, he proposed the model that the electrons are orbiting around the nucleus.
