Answer: Cu
Explanation: It is Cu because the origin of the word Copper comes from the latin word "Cuprum".
Protons and neutrons are the sub-atomic particles present in the nucleus of an atom where as electrons are present revolving round the nucleus in orbits. Electrons are negatively charged, protons are positively charged where as a neutron is a neutral species. It is the presence of electric charge that lead to the discovery of electrons (negative charge) and protons (positive charge), while it took time to discover neutral as they were electrically neutral species. Neutrons carrying no charge were not detected easily by passing electromagnetic radiations. Therefore, neutrons were the last of the three subatomic particles, to be discovered.
Answer:
6.7 x 10²⁶molecules
Explanation:
Given parameters
Mass of CO₂ = 4.9kg = 4900g
Unknown:
Number of molecules = ?
Solution:
To find the number of molecules, we need to find the number of moles first.
Number of moles = 
Molar mass of CO₂ = 12 + 2(16) = 44g/mol
Number of moles =
= 111.36mole
A mole of substance is the quantity of substance that contains the avogadro's number of particles.
1 mole = 6.02 x 10²³molecules
111.36 moles = 111.36 x 6.02 x 10²³molecules = 6.7 x 10²⁶molecules
Here we have to get the moles of hydrogen (H₂) consumed to form water (H₂O) from 1.57 moles of oxygen (O₂)
In this process 3.14 moles of H₂ will be consumed.
The balanced reaction between oxygen (O₂) and hydrogen (H₂); both of which are in gaseous state to form water, which is liquid in nature can be written as-
2H₂ (g) + O₂ (g) = 2H₂O (l).
Thus form the equation we can see that 1 mole of oxygen reacts with 2 moles of hydrogen to form 2 moles of water.
So, 1.57 moles of oxygen will consume (1.57×2) = 3.14 moles of hydrogen to form water.
Answer:
The empirical formula is = 
The molecular formula = 
Explanation:
% of C = 10.13
Molar mass of C = 12.0107 g/mol
% moles of C = 10.13 / 12.0107 = 0.8434
% of Cl = 89.87
Molar mass of Cl = 35.453 g/mol
% moles of Cl = 89.87 / 35.453 = 2.5349
Taking the simplest ratio for C and Cl as:
0.8434 : 2.5349
= 1 : 3
The empirical formula is = 
Molecular formulas is the actual number of atoms of each element in the compound while empirical formulas is the simplest or reduced ratio of the elements in the compound.
Thus,
Molecular mass = n × Empirical mass
Where, n is any positive number from 1, 2, 3...
Mass from the Empirical formula = 12*1 + 3*35.5 = 118.5 g/mol
Molar mass = 237 g/mol
So,
Molecular mass = n × Empirical mass
237 = n × 118.5
⇒ n ≅ 2
The molecular formula = 