Answer is (3) both mass number and atomic number.
The notation is ₅₅¹³⁷Cs. The Cs represents the chemical symbol of Caesium element. The subscript number at the left hand side of the symbol indicates the atomic number. Hence, atomic number of Cs is 55. The superscript number at the left hand side of the symbol shows the mass number. Hence, the mass number of the Cs is 137.
If the conjugate base of a molecule has a pKb of 1.4, the molecule should be a Weak Acid.
Notice this question gives us the pKb of the molecule, not the pKa. Because of this, the pH scale basically gets reversed, so lower numbers in pKb correlate with stronger bases, and higher numbers in pKb correlate with stronger acids - the exact opposite of the pH scale.
It's important to make sure you completely understand the terms of conjugate base, conjugate acid, pKb, pKa, and how they all relate. It's easy to mix up the meanings of these definitions.
Here are the two other pieces of information you need to know to correctly answer this question:
- Strong acids have a weak conjugate base.
- Strong bases have a weak conjugate acid.
So if the problem says you have a strong conjugate base, then the molecule must be a weak acid. To illustrate this, think of ammonium, NH4+. Ammonium is a weak acid, but the conjugate base of ammonium is ammonia, NH3, which is a reasonably good base.
Learn more about conjugate base here : brainly.com/question/22514615
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Answer:
a) 25%
b) 27.5 g
c) 90%
Explanation:
a) 75% fat-free by weight means 25% of the weight is made by fat.
b) 110 g ___ 100%
x ___ 25%
x = 27.5g
Each hot dog has 27.5g of fat.
c) 9 cal ___ 1 g fat
y ___ 27.5 g fat
y = 247.5 cal
275 cal ___ 100%
247.5 cal ___ z
z = 90%
90 % of the calories come from fat.
Answer:
D
Explanation:
Since [pKa = - log Ka]....hence..,the larger the Ka value,the stronger the acid is..so this means that the pKa is vice versa
Saying that the smaller the pKa value..the stronger the acid is.