The correct option is C. The amount of MgCl2. we know this because <span>no matter how much you increase KOH, if you dont increase Mgcl2, the amount of Mg(OH)2 remains the same. Hope this works for you</span>
Answer:
In order to react with 45 g of water 1.25 moles of CaC₂ are required.
Explanation:
Given data:
Moles of CaC₂ needed = ?
Mass of water = 45.0 g
Solution:
Chemical equation:
CaC₂ + 2H₂O → C₂H₂ + Ca(OH)₂
Number of moles of water:
Number of moles = mass/ molar mass
Number of moles = 45 g/ 18 g/mol
Number of moles = 2.5 mol
Now we will compare the moles of water and CaC₂ from balance chemical equation:
H₂O : CaC₂
2 : 1
2.5 : 1/2×2.5 =1.25 mol
In order to react with 45 g of water 1.25 moles of CaC₂ are required.
At STP, also known as standard temperature and pressure, 1 mole of a gas occupies 22.4 L. Since we are given with the volume of 6.3L, we calculate the amount of gas in mol.
n = (6.3L)/ (22.4L/mol) = 0.28125 mol
We are given with the mass of 6.7 g. Therefore, the molar mass or molecular weight of the gas is equal to,
6.7g/0.28125 mol = 23.82 g/mol
Answer:
The Atomic Number of the atom of an element whose model is given is "8" that is option no. 'C' in the question.
Explanation:
An Atom comprises of 3 basic structures that are Protons, Neutrons and Electrons. The central part is the Nucleus which contains protons and neutrons having positive charge and no charge respectively. The electrons are revolving around the nucleus in electronic shells having the negative charge.
<u><em>ATOMIC NUMBER: </em></u>
Atomic number is the number of protons present inside the nucleus of an atom and it determines the place of that particular atom in the <u>Periodic Table.</u>
In the model, given in the question, the nucleus contains 2 types of balls dark gray colored and light gray colored. The key at the bottom shows the dark gray colored ball as having a positive charge and thus it represents the atomic number for the given atom of element which is <u><em>EIGHT (8).</em></u>
So, the atomic number for the given atom is 8 which is element OXYGEN.
