Answer:
Across a period, effective nuclear charge increases as electron shielding remains constant. A higher effective nuclear charge causes greater attractions to the electrons, pulling the electron cloud closer to the nucleus which results in a smaller atomic radius. ... This results in a larger atomic radius.
Explanation:
Now lets d8
Answer:
w = -531 kJ
1. Work was done by the system.
Explanation:
Step 1: Given data
- Heat gained by the system (q): 687 kJ (By convention, when the system absorbs heat, q > 0).
- Change in the internal energy of the system (ΔU°): 156 kJ
Step 2: Calculate the work done (w)
We will use the following expression.
ΔU° = q + w
w = ΔU° - q
w = 156 kJ - 687 kJ
w = -531 kJ
By convention, when w < 0, work is done by the system on the surroundings.
Answer:
14.5 g silver
Explanation:
This is a problem using the stoichiometry of the reaction. First thing we need is the balanced equation:
Zn + 2 AgNO3 ----------------------- 2 Ag + Zn(NO3)2
We know that 14.6 g of Zn did not reacted, then we can calculate the amount of Zn reacted and do the calculation given the above reaction.
amount Zn reacted: 19.0 -14.6 g Zn = 4.4 g Zn
atomic weight of Zn: 65.37 g/mol
mol Zn reacted: 4.4 g Zn x ( 1 mol Zn/ 65.37 g Zn) = 0.067 mol Zn
We know from the balanced equation that moles of Ag are produced from 1 mol Zn therefore the mol of Ag produced are:
0.067 mol Zn x 2 mol Ag/ 1mol Zn = 0.135 mol Ag
and the mass of silver then will be given by multiplying by the atomic weight of silver:
0.135 mol Ag x 107.9 g/mol = 14.5 g Ag
<span>The law of conservation of energy states that energy can neither be created nor destroyed - it can only be converted from one form to another. It basically means that energy can't just appear, but has to be converted from existing energy; for example, the chemical energy in petrol is turned into electrical energy to power a car.Remember the total energy of universe is constant,,and no more energy can be drawn from out if we collect all universe's energy at a single point(its the big bang energy splitted during </span>
Solid carbon reacts with oxygen gas to form carbon dioxide gas.
The balanced chemical equation for this reaction:
