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The pH scale for acidity is defined by pH = − log₁₀[H⁺] where [H⁺] is the concentration of hydrogen ions measured in moles per liter (M). A solution has a pH of 2.55. Find the hydrogen ion concentration.
Answer: -
0.003 M
Explanation: -
pH = − log₁₀[H⁺]
Thus the hydrogen ion concentration [H⁺] = 
= 
= 0.003 M
Answer:

Explanation:
Hello,
In this case, we consider that at STP conditions (273 K and 1 atm) we know that the volume of 1 mole of a gas is 22.4 L, thereby, for 83.4 L, the resulting moles are:

This is a case in which we apply the Avogadro's law which relates the volume and the moles as a directly proportional relationship.
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Answer:
0.73 mol
Explanation:
No. of moles(n)= Given mass/molar mass.
Given mass=124.7g
Molar mass of Ba(OH)2= Molar mass of (Barium+2Oxygen+2Hydrogen)=137+32+2=171g
No. of moles= 124.7g/171g=0.73 mol
Answer:
Ionic bonds are formed through the exchange of valence electrons between atoms, typically a metal and a nonmetal. The loss or gain of valence electrons allows ions to obey the octet rule and become more stable. Therefore, ions combine in ways that neutralize their charges.
Explanation:
Charged particles or ionic particles?