Answer:
(a) (i) All the elements of a group have similar chemical properties because they have same no. of valence electrons in their outermost shell. (ii) All the elements of a period have different chemical properties because they have different no. of valence electrons in their atoms.
Answer:
0.054 mol O
Explanation:
<em>This is the chemical formula for acetic acid (the chemical that gives the sharp taste to vinegar): CH₃CO₂H. An analytical chemist has determined by measurements that there are 0.054 moles of carbon in a sample of acetic acid. How many moles of oxygen are in the sample?</em>
<em />
Step 1: Given data
- Chemical formula of acetic acid: CH₃CO₂H
- Moles of carbon in the sample: 0.054 moles
Step 2: Establish the appropriate molar ratio
According to the chemical formula, the molar ratio of C to O is 2:2.
Step 3: Calculate the moles of oxygen in the sample
We will use the molar ratio to determine the moles of oxygen accompanying 0.054 moles of carbon.
0.054 mol C × (2 mol O/2 mol C) = 0.054 mol O
Answer:
The concentration of this sodiumhydroxide solutions is 0.50 M
Explanation:
Step 1: Data given
Mass of sodium hydroxide (NaOh) = 8.0 grams
Molar mass of sodium hydroxide = 40.0 g/mol
Volume water = 400 mL = 0.400 L
Step 2: Calculate moles NaOH
Moles NaOH = mass NaOH / molar mass NaOH
Moles NaOH = 8.0 grams / 40.0 g/mol
Moles NaOh = 0.20 moles
Step 3: Calculate concentration of the solution
Concentration solution = moles NaOH / volume water
Concentration solution = 0.20 moles / 0.400 L
Concentration solution = 0.50 M
The concentration of this sodiumhydroxide solutions is 0.50 M
Answer:The ideal gas law is represented mathematically as: PV=nRT. P- pressure, V- volume, n-number of moles of gas, R- ideal gas constant, T- temperature.
Explanation:The ideal gas law is used as a prediction of the behavior of many gases, when subjected to different conditions.
he ideal gas law has so many limitations.
An increase in the pressure or volume, decreases the number of moles and temperature of the gas.
Empirical laws that led to generation of the ideal gas laws, considered two variables and keeping the others constant. This empirical laws include, Boyle's law, Charles's law, Gay Lusaac's law and Avogadro's law.
