Answer:
Mass of 1 mole of copper is 63.83 g.
0.03916 moles of copper atoms have a mass equal to the 2.5 grams of copper penny.
Explanation:
Mass of 1 copper atom,m = 

Mass of 1 mole of copper :
= 
Mass of 1 mole of copper = 63.83 g
Mass of copper penny = 2.5 g
Atomic mass of copper = 63.83 g/mol
Moles of copper in 2.5 g of copper penny:

0.03916 moles of copper atoms have a mass equal to the 2.5 grams of copper penny.
Answer:
V₁ = 374.71 mL
Explanation:
Given data:
Initial volume of gas= ?
Initial temperature = 22°C
Final temperature = 86°C
Final volume = 456 mL
Solution:
Initial temperature = 22°C (22+273 = 295 k)
Final temperature = 86°C (86+273 = 359 k)
The given problem will be solve through the Charles Law.
According to this law, The volume of given amount of a gas is directly proportional to its temperature at constant number of moles and pressure.
Mathematical expression:
V₁/T₁ = V₂/T₂
V₁ = Initial volume
T₁ = Initial temperature
V₂ = Final volume
T₂ = Final temperature
Now we will put the values in formula.
V₁/T₁ = V₂/T₂
V₁ = V₂T₁ /T₂
V₁ = 456 mL × 295 K / 359 k
V₁ = 134520 mL.K / 359 k
V₁ = 374.71 mL
Ans: Calcium sulfate.
K2SO4 (aq) + Ca(NO3)2 (aq) ⇒ 2KNO3 (aq) + CaSO4 (s)
The Rutherford–Bohr model of the hydrogen atom (Z = 1) or a hydrogen-like ion (Z > 1). In this model it is an essential feature that the photon energy (or frequency) of the electromagnetic radiation emitted (shown) when an electron jumps from one orbital to another, be proportional to the mathematical square of atomic charge (Z2). Experimental measurement by Henry Moseley of this radiation for many elements (from Z = 13 to 92) showed the results as predicted by Bohr. Both the concept of atomic number and the Bohr model were thereby given scientific credence. The atomic number is the number of _z_ an atom.