Answer:
A chemical change is a change in the chemical makeup of a substance and results in a new substance. Ice and water both have the same chemical makeup - ice is just a different state and has the same atoms but in an expanded form.
Explanation:
Answer:
pOH = 4.8
pH = 9.2
Explanation:
Given data:
Hydrogen ion concentration = 6.3×10⁻¹⁰M
pH of solution = ?
pOH of solution = ?
Solution:
Formula:
pH = -log [H⁺]
[H⁺] = Hydrogen ion concentration
We will put the values in formula to calculate the pH.
pH = -log [6.3×10⁻¹⁰]
pH = 9.2
To calculate the pOH:
pH + pOH = 14
We will rearrange this equation.
pOH = 14 - pH
now we will put the values of pH.
pOH = 14 - 9.2
pOH = 4.8
Answer:
0.007 mol
Explanation:
We can solve this problem using the ideal gas law:
PV = nRT
where P is the total pressure, V is the volume, R the gas constant, T is the temperature and n is the number of moles we are seeking.
Keep in mind that when we collect a gas over water we have to correct for the vapor pressure of water at the temperature in the experiment.
Ptotal = PH₂O + PO₂ ⇒ PO₂ = Ptotal - PH₂O
Since R constant has unit of Latm/Kmol we have to convert to the proper unit the volume and temperature.
P H₂O = 23.8 mmHg x 1 atm/760 mmHg = 0.031 atm
V = 1750 mL x 1 L/ 1000 mL = 0.175 L
T = (25 + 273) K = 298 K
PO₂ = 1 atm - 0.031 atm = 0.969 atm
n = PV/RT = 0.969 atm x 0.1750 L / (0.08205 Latm/Kmol x 298 K)
n = 0.007 mol
Answer : q = 6020 J, w = -6020 J, Δe = 0
Solution : Given,
Molar heat of fusion of ice = 6020 J/mole
Number of moles = 1 mole
Pressure = 1 atm
Molar heat of fusion : It is defined as the amount of energy required to melt 1 mole of a substance at its melting point. There is no temperature change.
The relation between heat and molar heat of fusion is,
(in terms of mass)
or, 
(in terms of moles)
Now we have to calculate the value of q.
When temperature is constant then the system behaves isothermally and Δe is a temperature dependent variable.
So, the value of 
Now we have to calculate the value of w.
Formula used : 
where, q is heat required, w is work done and 
is internal energy.
Now put all the given values in above formula, we get
w = -6020 J
Therefore, q = 6020 J, w = -6020 J, Δe = 0
Answer:
Biopolymers are natural polymers produced by the cells of living organisms. Biopolymers consist of monomeric units that are covalently bonded to form larger molecules. There are three main classes of biopolymers, classified according to the monomers used and the structure of the biopolymer formed: polynucleotides, polypeptides, and polysaccharides.
Explanation:
