Answer:
pH = 4.25
Explanation:
A solution composed of a weak acid and its conjugate base is a <em>buffer solution</em>. To calculate the pH of a buffer solution we use the Henderson-Hasselbach equation:
pH = pKa + log ([conjugate base]/[weak acid]
In this case, we have the following data:
[conjugate base] = [sodium benzoate] = 0.230 M
[weak acid] = [benzoic acid] = 0.205 M
The pKa of benzoic acid is 4.2. So, we introduce the data in the equation:
pH = 4.2 + log (0.230 M/0.205 M) = 4.2 + 0.050 = 4.25
B. a physical combination of two or more different materials.
Answer : Option D) Covalent bond.
Explanation : The bond formed when electrons are shared is called a covalent bond.
A covalent bond which is also called as molecular bond, is a chemical bond which involves mainly the sharing of electron pairs between atoms. These electron pairs are called as shared pairs or bonding pairs, which are stable balance of attractive and repulsive forces between atoms, when these bonding pairs share electrons, it is called as covalent bonding.
Covalent bonding is usually seen in non-metals which share their electrons while bonding.
The percent yield : 4. 84.58%
<h3>Further explanation</h3>
Reaction
CaCO₃ ⇄ CaO+CO₂
mass CaCO₃ = 2.3 × 10³ g
mol CaCO₃ (MW=100.0869 g/mol) :
From the equation, mol CaCO₃ : CaO = 1 : 1, so mol CaO=22.98
mass CaO(MW=56.0774 g/mol)⇒ (theoretical) :
The percent yield :
Answer:
Explanation:
Hello!
In this case, according to the given balanced chemical reaction:
We can see there is 1:1 between benzene and chlorobenzene as the relavant product; thus, since the molar mass of benzene is 78.11 g/mol and that of chlorobenzene is 112.55 g/mol, the theoretical yield for this reaction turns out:
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