Answer:
use coefficients and subscripts to determine how many atoms are in a compound. If there is no subscript or coefficient, assume it is 1. If there is a coefficient, multiply it with the subscripts. For counting cations and anions, determine first which is the anion and cation (anion = nonmetal, cation = metal), then count the number of that ion.
Example:
NaCl
one atom of Na, one atom of Cl. Since Na is a metal, it is a cation. Cl is a nonmetal, so it is an anion.
2CaCl2
2 atoms of Ca, 4 atoms of Cl. There are 2 cations, since Na is a metal, and 4 anions since Cl is a nonmetal
<u>Answer:</u> The final temperature of the coffee is 43.9°C
<u>Explanation:</u>
To calculate the final temperature, we use the equation:

where,
q = heat released = 
m = mass of water = 10.0 grams
C = specific heat capacity of water = 4.184 J/g°C
= final temperature = ?
= initial temperature = 20°C
Putting values in above equation, we get:

Hence, the final temperature of the coffee is 43.9°C
%yield = 88.5%
<h3>Further explanation</h3>
Given
Reaction
Cu(s) + 2 AgNO₃(aq) → Cu(NO₃)₂(aq) + 2Ag(s)
Required
The percent yield
Solution
mol AgNO₃(MW=169,87 g/mol) :
= mass : MW
= 127 : 169.87
= 0.748
mol Ag from equation :
= 2/2 x mol AgNO₃
= 2/2 x 0.748
= 0.748
Mass Ag (theoretical) :
= mol x Ar Ag
= 0.748 x 108
= 80.784
% yield = (actual/theoretical) x 100%
%yield = 71.5/80.784 x 100%
<em>%yield = 88.5%</em>
There would be 55.8 g present
Answer:
Here's what I get
Explanation:
The modern periodic law states that the physical and chemical properties of the elements are periodic functions of their atomic numbers.