1. Lemon juice (pH 2.2) = Acidic
2. Salt solution (pH 7) = Neutral
3. Baking soda (pH 9) = Alkaline
4. Bleach (pH 13) = Alkaline
5. Tomato juice (pH 4) = Acidic
6. Gastric juices (pH 1) = Acidic
<h3>Explanation: </h3>
The pH scale measures how acidic or alkaline a substance is. The pH scale ranges from <u>0 to 14.</u>
A pH of 7 is neutral.
Acidic substances have pH less than 7.
Alkaline(Base) substances have a pH greater than 7
Hence, the given samples can be categorized as acidic, basic or neutral based on their pH values.
1. Lemon juice (pH 2.2 < 7) = Acidic
2. Salt solution (pH 7 = 7) = Neutral
3. Baking soda (pH 9 > 7) = Alkaline
4. Bleach (pH 13 >7) = Alkaline
5. Tomato juice (pH 4 < 7) = Acidic
6. Gastric juices (pH 1 < 7) = Acidic
Answer:
We will use ideal gas equation in this problem
PV = nRT
Where
P = pressure of gas or air = ?
V = volume of air = volume of pressure cooker = 5.68 L
T = temperature = 394 K
n = moles of air = 0.355
R = ideal gas equation = 0.0821 L atm / mol K
Putting values
Pressure = nRT / V = 0.355 X 0.0821 X 394 / 5.68 = 2.02 atm.
Actual question from source:-
A 3.96x10-4 M solution of compound A exhibited an absorbance of 0.624 at 238 nm in a 1.000 cm cuvette. A blank had an absorbance of 0.029. The absorbance of an unknown solution of compound A was 0.375. Find the concentration of A in the unknown.
Answer:
Molar absorptivity of compound A = 
Explanation:
According to the Lambert's Beer law:-
Where, A is the absorbance
l is the path length
is the molar absorptivity
c is the concentration.
Given that:-
c = 
Path length = 1.000 cm
Absorbance observed = 0.624
Absorbance blank = 0.029
A = 0.624 - 0.029 = 0.595
So, applying the values in the Lambert Beer's law as shown below:-
<u>Molar absorptivity of compound A = </u>
Explanation:
Matter can be classified into two broad categories: pure substances and mixtures. ... A material composed of two or more substances is a mixture. Elements and compounds are both examples of pure substances. A substance that cannot be broken down into chemically simpler components is an elementOne useful way of organizing our understanding of matter is to think of a hierarchy that extends down from the most general and complex to the simplest and most fundamental (Figure 3.4.1 ). Matter can be classified into two broad categories: pure substances and mixtures. A pure substance is a form of matter that has a constant composition (meaning that it is the same everywhere) and properties that are constant throughout the sample (meaning that there is only one set of properties such as melting point, color, boiling point, etc. throughout the matter). A material composed of two or more substances is a mixture. Elements and compounds are both examples of pure substances. A substance that cannot be broken down into chemically simpler components is an element. Aluminum, which is used in soda cans, is an element. A substance that can be broken down into chemically simpler components (because it has more than one element) is a compound. For example, water is a compound composed of the elements hydrogen and oxygen. Today, there are about 118 elements in the known universe. In contrast, scientists have identified tens of millions of different compounds to date.
