Given:
AgCl (s) ===> Ag+ (aq) + Cl- (aq)
- negative entropy
H2O(g) ===> H2O(l)
- positive entropy
2Na (s) + Cl2 (g) ===> 2NaCl (s)
- positive entropy
Br2(l) ===> Br2 (s)
-positive entropy
They are identified to have positive or negative values of entropy based on the phases of the reactants and products.
<span>
Low pH means the solution is acidic; if the solution is acidic, that
means that there are hydronium ions in solution (H3O+). For example,
hydrochloric acid dissolves into H+ ions and Cl- ions, and the H+ ions
rreact with water like this:
H+ + H2O --> H3O+
If you want to get mathematical, pH is defined as the negative log of the concentration of hydronium ions.
Thus, if there are a lot of hydronium ions, the solution will have a low, or acidic, pH. Hope this helps^-^</span>
A) Mass Number
B) Protons and Electrons
C) (I think group but I'm not 100% sure on this...)
D) 12 (To work out the number of neutrons you do MASS number - ATOMIC number aka the number of protons so in this case you'd do 23-11=12)
Hope this helps
7.5 ppm
<h3>Further explanation</h3>
Given
1000 g of water
0.0075g of Ca²⁺ ion
Required
the concentration in ppm by mass of Ca²⁺
Solution
ppm = part per million
solvent = water ⇒ ppm = 1 mg/L(water density is 1 kg / L) or mg/kg
Convert g to mg of Ca²⁺ ion :
0.0075 g = 7.5 x 10⁻³ g = 7.5 mg
Convert g to kg of water :
1000 g = 1 kg water
So the concentration of Ca²⁺ ion :
= 7.5 mg / 1 kg
= 7.5 ppm
Answer:
The mass of gold is found to be 310.34 g.
Explanation:
We have:
Specific heat of gold = C = 0.130 J/g.°C
Heat = H = 468 J
Change in Temperature = ΔT = 33.2 °C - 21.6 °C = 11.6 °C
Now, to find mass of gold we first calculate the amount of heat required to heat the unit mass of gold to specified temperature:
Mass Specific Heat = C * ΔT
Mass Specific Heat = (0.130 J/g.°C)(11.6 °C)
Mass Specific Heat = 1.508 J/g
Now, for the mass of gold (m):
mass of gold = Heat/Mass Specific Heat
mass of gold = 468 J/1.508 J/g
<u>mass of gold = 310.34 g</u>
