Ions have an extra or lost an electron. Isotopes have different numbers of neutrons.
Answer:
The chemical change in matter is results in a change in its identity and properties.
Explanation:
There are toe type of changes physical change and chemical change.
The chemical change change in matter lead to lost its identity and properties.
Chemical change:
The changes, that occur due to change in the composition of a substance and result in a different compound is known as chemical change.
These changes are irreversible
These changes occur due to chemical reactions
These may not be observed with naked eye
Example:
Combustion of fuel or wood: that oil or wood convert into energy, CO2 and ash in case of wood
Boiling of egg: that change the chemical composition of protein in the egg .
The reaction of Hydrogen and oxygen:
H 2 (g) + O 2 (g) -------------------------------------> 2H 2O (l)
<u>Answer:</u> The temperature of the system is 273 K
<u>Explanation:</u>
To calculate the number of moles, we use the equation:
Given mass of carbon dioxide = 1 lb = 453.6 g (Conversion factor: 1 lb = 453.6 g)
Molar mass of carbon dioxide = 44 g/mol
Putting values in above equation, we get:

To calculate the temperature of gas, we use the equation given by ideal gas equation:
PV = nRT
where,
P = Pressure of carbon dioxide = 200 psia = 13.6 atm (Conversion factor: 1 psia = 0.068 atm)
V = Volume of carbon dioxide =
(Conversion factor:
)
n = number of moles of carbon dioxide = 10.31 mol
R = Gas constant = 
T = temperature of the system = ?
Putting values in above equation, we get:

Hence, the temperature of the system is 273 K
Answer is: the hydronium ion concentratio is 1.71×10⁻⁷ mol/dm³ and pH<6.76.
The Kw (the ionization constant of water) at 40°C is 2.94×10⁻¹⁴ mol²/dm⁶ or 2.94×10⁻¹⁴ M².
Kw = [H₃O⁺] · [OH⁻].
[H₃O⁺] = [OH⁻] = x.
Kw = x².
x = √Kw.
x = √2.94×10⁻¹⁴ M².
x = [H₃O⁺] = 1.71×10⁻⁷ M; concentration of hydronium ion.
pH = -log[H₃O⁺].
pH = -log(1.71×10⁻⁷ M).
pH = 6.76.
pH (potential of hydrogen) is a numeric scale used to specify the acidity or basicity an aqueous solution.