Answer:
A. False.
Every substance contains the same number of molecules i.e 6.02x10^23 molecules
B. False.
Mass conc. = number mole x molar Mass
Mass conc. of 1mole of N2 = 1 x 28 = 28g
Mass conc. of 1mol of Ar = 1 x 40 = 40g
The mass of 1mole of Ar is greater than the mass of 1mole of N2
C. False.
Molar Mass of N2 = 2x14 = 28g/mol
Molar Mass of Ar = 40g/mol
The molar mass of Ar is greater than that of N2.
Explanation:
Answer: With atomic number 20, calcium atoms have 20 positive protons, and the ion has only 18 electrons, which means the net charge is +2. Calcium ions are essential for muscle contractions, nerve impulses, and bone maintenance.
:
The heat released by the water when it cools down by a temperature difference AT
is Q = mC,AT
where
m=432 g is the mass of the water
C, = 4.18J/gºC
is the specific heat capacity of water
AT = 71°C -18°C = 530
is the decrease of temperature of the water
Plugging the numbers into the equation, we find
Q = (4329)(4.18J/9°C)(53°C) = 9.57. 104J
and this is the amount of heat released by the water.
Answer:
FeCl₃
Explanation:
4FeCl₃ + 3O₂ => 2Fe₂O₃+ 6Cl₂
Given => 7moles 9moles
A simple way to determine which reagent is the limiting reactant is to convert all given data to moles then divide by the respective coefficients of the balanced equation. The smaller value will be the limiting reactant.
4FeCl₃ + 3O₂ => 2Fe₂O₃+ 6Cl₂
Given => 7/4 = 1.75* 9/3 = 3
*Smaller value => FeCl₃ is limiting reactant.
NOTE: However, when working problems, one must use original mole values given.