Answer:
Strong acid
Explanation:
An acid is a substance that interacts with water to produce excess hydroxonium ions in an aqueous solution.
Hydroxonium ions are formed as a result of the chemical bonding between the oxygen of water molecules and the protons released by the acid due to its ionisation. This makes aqueous solution of acids conduct electricity.
A strong acid is one that ionizes almost completely. Examples are:
1. Hydrochloric acid
2. Tetraoxosulphate (VI) acid
3. Trioxonitrate (V) acid
4. Hydroiodic acid
5. Hydrobromic acid
Answer:
Time = 0.929s = 0.93s (2 s.f)
Explanation:
Rate constant, k = 34.1 M^-1s^-1
Initial Concentration, [A]o = 0.100M
Time = ?
Final Concentration [A] = 0.0240M
The parameters are represented in the following equation as;
1/[A] = kt + 1/[A]o
kt = 1/[A] - 1/[A]o
kt = 1/0.0240 - 1/0.1
kt = 31.67
t = 31.67 / 34.1
t = 0.929s = 0.93s (2 s.f)
Answer:
8740 joules are required to convert 20 grams of ice to liquid water.
Explanation:
The amount of heat required (
), measured in joules, to convert ice at -50.0 ºC to liquid water at 0.0 ºC is the sum of sensible heat associated with ice and latent heat of fussion. That is:
![Q = m\cdot [c\cdot (T_{f}-T_{o})+L_{f}]](https://tex.z-dn.net/?f=Q%20%3D%20m%5Ccdot%20%5Bc%5Ccdot%20%28T_%7Bf%7D-T_%7Bo%7D%29%2BL_%7Bf%7D%5D)
(1)
Where:
- Mass, measured in grams.
- Specific heat of ice, measured in joules per gram-degree Celsius.
, 
- Temperature, measured in degrees Celsius.
- Latent heat of fussion, measured in joules per gram.
If we know that 
, 
, 
, 
and 
, then the amount of heat is:
![Q = (20\,g)\cdot \left\{\left(2.06\,\frac{J}{g\cdot ^{\circ}C} \right)\cdot [0\,^{\circ}C-(-50\,^{\circ}C)]+334\,\frac{J}{g} \right\}](https://tex.z-dn.net/?f=Q%20%3D%20%2820%5C%2Cg%29%5Ccdot%20%5Cleft%5C%7B%5Cleft%282.06%5C%2C%5Cfrac%7BJ%7D%7Bg%5Ccdot%20%5E%7B%5Ccirc%7DC%7D%20%5Cright%29%5Ccdot%20%5B0%5C%2C%5E%7B%5Ccirc%7DC-%28-50%5C%2C%5E%7B%5Ccirc%7DC%29%5D%2B334%5C%2C%5Cfrac%7BJ%7D%7Bg%7D%20%5Cright%5C%7D)
8740 joules are required to convert 20 grams of ice to liquid water.
Answer: 4.96 moles
Explanation:
C5H12 is the chemical formula for pentane, the fifth member of the alkane family.
Given that,
number of moles of C5H12 = ?
Mass in grams = 357.4 g
Molar mass of C5H12 = ?
To get the molar mass of C5H12, use the atomic mass of carbon = 12g; and Hydrogen = 1g
i.e C5H12 = (12 x 5) + (1 x 12)
= 60g + 12g
= 72g/mol
Now, apply the formula
Number of moles = Mass / molar mass
Number of moles = 357.4g / 72g/mol
= 4.96 moles
Thus, 4.96 moles of C5H12 that are contained in 357.4 g of the compound.
Answer is: the third reaction.
Elements in this chemical reaction do not change their oxidation number. Hydrogen has oxydation number +1, sulfur oxidation number is +6, oxygen has oxidation number -2 and barium has +2 on both sides of chemical reaction. In other reactions elements change their oxidation numbers.
