1 mol of any substance is made of 6.022 x 10²³ units.
When its 1 mol of a formula, its made of 6.022 x 10²³ formula units
Therefore if 6.022 x 10²³ formula units of CeI₃ make up 1 mol of CeI₃
Then 9.42 x 10²¹ formula units make up - 1/(6.022 x 10²³) x (9.42 x 10²¹) = 0.0156 mol of CeI₃
Therefore number of moles of CeI₃ - 0.0156 mol
Answer:
Explanation:
Reflection of trees in clear water and reflection of mountains in a lake. Wings of most butterflies are identical on the left and right sides. Some human faces are the same on the left and right side. People can also have a symmetrical mustache.
Answer:
0.5 mole CO2=0. 5×44=22 gm.
Answer:
16.791 grams
Explanation:
The density formula is:
Rearrange the formula for m, the mass. Multiply both sides of the equation by v.
The mass of the gold nugget can be found by multiplying the density and volume. The density is 19.3 grams per cubic centimeter and the volume is 0.87 cubic centimeters.
Substitute the values into the formula.
Multiply. Note that the cubic centimeters, or cm³ will cancel each other out.
The mass of the gold nugget is 16.791 grams.
Question 1. What one factor identifies an atom as a specific element? Answer: the number of protons. Remember that the atoms of a same element have the same number of protons, and the atoms of different elements cannot have the same number of protons. That permits to order the elements according to the atomic number (number of protons) in the periodic table. Question 2.An atom of fluorine has an atomic number of 9 and an atomic mass of 19. The atom contains Answer: 9 protons, 9 electrons, and 10 neutrons : because the atomic number is the number of protons, the number of electrons must be equal to the number of protons (because the atom is neutral), and the mass number is the number or protons plus the number of neutrons: 9 protons + 10 neutrons = 19 mass number (atomic mass). Question 33.Experiments with cathode ray tubes led to a new model of the atom, sometimes called the \"plum pudding\" model, because of the discovery of the <span>. Answer. electron ... when electron was discovered JJ Thompson proposed the plum pudding model, in which the atom was a solid positively charged sphere with electrons distributed inside it.</span>
