Answer:
an element.
Explanation:
When all the atoms contain a nucleus with the same amount of protons then each atom is classified as the same element. Hence multiple atoms and a larger quantity of atoms of the same element is still just the same single element.
Number of atoms in 1.4 mol of Phosphorus trifluoride (PF₃) : 8.428 x 10²³
<h3>Further explanation </h3>
The mole is the number of particles(molecules, atoms, ions) contained in a substance
1 mol = 6.02.10²³ particles
Can be formulated
N=n x No
N = number of particles
n = mol
No = Avogadro's = 6.02.10²³
1.4 mol of Phosphorus trifluoride (PF₃), number of atoms :
Answer:
1. Potassium, K.
2. Calcium, Ca.
3. Gallium, Ga.
4. Carbon, C.
5. Bromine, Br.
6. Barium, Ba.
7. Silicon, Si.
8. Gold, Au.
Explanation:
Atomic radius can be defined as a measure of the size (distance) of the atom of a chemical element such as hydrogen, oxygen, carbon, nitrogen etc, typically from the nucleus to the valence electrons. The atomic radius of a chemical element decreases across the periodic table, typically from alkali metals (group one elements such as hydrogen, lithium and sodium) to noble gases (group eight elements such as argon, helium and neon). Also, the atomic radius of a chemical element increases down each group of the periodic table, typically from top to bottom (column).
Additionally, the unit of measurement of the atomic radius of chemical elements is picometers (1 pm = 10 - 12 m).
1. Li or K: the atomic radius of lithium is 167 pm while that of potassium is 243 pm.
2. Ca or Ni: the atomic radius of calcium is 194 pm while that of nickel is 149 pm.
3. Ga or B: the atomic radius of gallium is 136 pm while that of boron is 87 pm.
4. O or C: the atomic radius of oxygen is 48 pm while that of carbon is 67 pm.
5. Cl or Br: the atomic radius of chlorine is 79 pm while that of bromine is 94 pm.
6. Be or Ba: the atomic radius of berryllium is 112 pm while that of barium is 253 pm.
7. Si or S: the atomic radius of silicon is 111 pm while that of sulphur is 88 pm.
8. Fe or Au: the atomic radius of iron is 156 pm while that of gold is 174 pm.
The reactants are found on the Left of the arrow :)
Answer: Cl₃ > F₂ > O₂ > Ne
Explanation:
1) All the gases are at the same temperature and pressure: STP (O°, 1 atm).
2) All the gases are represented by one molecule (or mole of molecules, it is the same for our puroposes).
3) As per Avogadro's law and the ideal gas equation, the same number of particles (of any gas) occupy the same volume at the same temperature and pressure.
For example, at STP the volume of 1 mol of gas is 22.4 liter.
4) Since, density is equal to mass / volume, and you assume the same number of molecules of each gas, the order of the densities is the same that the order of the molar masses.
5) Then, you just need to state the molar mass of each gas and order in decreasing order of molar mass to have the correct order for density.
6) Molar masses:
i) Ne: 20.180 g/mol
ii) O₂: 2× 15.999 g/mol = 31.998 g/mol
iii) F₂: 2×18.998 g/mol = 37.996 g/mol
iv) Cl₃: 3×35.453 g/mol = 106.359
7) Then the order is: 106.359 > 37.996 > 31.998 > 20.18 ⇒ is Cl₃ > F₂ > O₂ > Ne.
Note: the values calculate are not of densities but of molar masses. The order is what is the same.
