Answer:
0.5 × 10²³ atoms of iodine
Explanation:
Given data:
Mass of calcium iodide = 12.75 g
Number of atoms of iodine = ?
Solution:
First of all we will calculate the number of moles of calcium iodide.
Number of moles = mass/ molar mass
Number of moles = 12.75 g/ 293.9 g/mol
Number of moles = 0.04 mol
In one mole of calcium iodide there are two moles of iodine.
Thus in 0.04 moles:
0.04 mol × 2 = 0.08 moles of iodine
Now we will use the Avogadro number:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
1 mole = 6.022 × 10²³ atoms
0.08 moles of iodine × 6.022 × 10²³ atoms / 1 mol
0.5 × 10²³ atoms of iodine.
Answer:Photon
Explanation: hope it helped
The statement that would be held true for an acidic solution would be option C. The molarity or concentration of the hydronium ions would be more than that of the hydroxide ions. As the acidity of a solution increases as there is a greater amount of H+ or H3O+ ions present, within it. This is will give us a low pH and thus is quite acidic.
If the concentrations of the OH- and H3O+ are the same then the solution would be neutral, and if the opposite is true. The concentration of OH- is more than H3O+ than the solution would be basic.
Answer:
The diagram is incorrect because there is only a single type of particle at the center of the atom.
Explanation:
The small circle at the centre of the sphere which contains six light gray spheres and six dark gray spheres represents the nucleus of the atom which is found at the centre of the atom.
The nucleus contains only one type of particle which is the proton. Hence the representation of two particles at the centre of the circle makes the model incorrect.
1 mole of any gas occupy 22.4 L at STP (standard temperature and pressure, 0°C and 1 atm).
Let given gases be 1 mole. So their volumes will be the same, 22.4 liters.
Density is the ratio of mass to volume.
By formula; density= mass/volume; d=m/V
To find out masses of gases, do the mole calculation.
By formula; mole= mass/molar mass; n= m/M; m= n*M
Molar masses are calculated as
1. C₂H₆ (ethane) = 2*12 g/mol + 6*1 g/mol= 30 g/mol
2. NO (nitrogen monoxide) = 1*14 g/mol + 1*16 g/mol= 30 g/mol
3. NH₃ (ammonia) = 1*14 g/mol + 3*1 g/mol= 17 g/mol
4. H₂O (water) = 2*1 g/mol + 1*16 g/mol= 18 g/mol
5. SO₂ (sulfur dioxide) = 1*32 g/mol + 2*16 g/mol= 64 g/mol
Use Periodic Table to get atomic mass of elements.
Since their volumes are equal, compounds having the same molar mass will have the same density.
Recall the formula d= m/V.
Ethane and nitrogen monoxide have the same density.
The answer is C₂H₆ and NO.
