Explanation :
The balanced chemical reaction will be,

By the stiochiometry, 3 moles of solid copper(II)oxide react with 2 moles of ammonia gas to give 3 moles of copper metal, 1 mole of nitrogen gas and 3 moles of liquid water.
The states of matter of each elements and compound is,
Copper(II)oxide is in solid state
Ammonia is in gaseous state
Copper metal is in solid state
Nitrogen is in gaseous state
Water is in liquid state
Answer:
Electrons arrangement change is almost constant down the group, hence nuclear charge is almost constant.
But the energy levels on which electrons are arranged increase down the group, hence shielding or screening effect increases.
Answer:
The answer is
<h2>0.784 g/mL</h2>
Explanation:
The density of a substance can be found by using the formula
<h3>

</h3>
From the question
mass of liquid = 9.8 g
volume = 12.5 mL
The density is

We have the final answer as
<h3>0.784 g/mL</h3>
Hope this helps you
Answer: The atomic weight of silver is 107.87 amu
Explanation:
Mass of isotope silver-107 = 106.91 amu
% abundance of isotope silver -107 = 51.84% = 
Mass of isotope silver-109 = 108.90 amu
% abundance of isotope silver-109 = 48.16% = 
Formula used for average atomic mass of an element :

![A=\sum[(106.91\times 0.5184)+(108.90\times 0.4816)]](https://tex.z-dn.net/?f=A%3D%5Csum%5B%28106.91%5Ctimes%200.5184%29%2B%28108.90%5Ctimes%200.4816%29%5D)

Thus atomic weight of silver is 107.87 amu
Answer:
6 electrons
Explanation:
The principal quantum number n; describes the energy level and here, it is 2.
The azimuthal or secondary quantum number l is given as 1, we are describing the p-orbital
The magnetic quantum number is -1, and we have 3 sub-orbitals here:
It is a 2p-suborbital
So; in each sub orbital we have 2 electrons
The number of electrons that can be described here = 2 x 3 = 6 electrons.