Answer:
d) They're studying something for which they cant do an experiment
Explanation:
Answer:
Increasing atomic number - True
Explanation:
The modern table is based on Mendeleev’s table, except the modern table arranges the elements by increasing atomic number instead of atomic mass.
The Atomic number is the number of protons in an atom, and this number is unique for each element. For example, Hydrogen has an atomic number of 1, Calcium has an atomic number of 20.
In the modern periodic table the elements are further arranged into:
- rows, called periods, in order of increasing atomic number. Elements in the same periods have the same number of shells.
- vertical columns, called groups, where the elements have similar properties. Elements in the same group has the same number of valency (outermost number of electrons)
Answer:
A. 2 bonds
Explanation:
If you see a charch of ci20 it would easily show the answer.
Answer:
14.8 × 10²³ molecules
Explanation:
Given data:
Mass of sulfuric acid = 240 g
Number of molecules = ?
Solution:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
For example,
18 g of water = 1 mole = 6.022 × 10²³ molecules of water
1.008 g of hydrogen = 1 mole = 6.022 × 10²³ atoms of hydrogen
Number of moles of sulfuric acid
<em>Number of moles = mass/ molar mass</em>
Number of moles = 240 g/ 98 g/mol
Number of moles = 2.45 mol
Number of molecules:
1 mole = 6.022 × 10²³ molecules
2.45 × 6.022 × 10²³ molecules
14.8 × 10²³ molecules
Answer:
Mass = 153.48 g
Explanation:
Given data:
Volume of solution = 2.50 L
Molarity = 0.48 M
Mass required = ?
Solution:
Molarity = number of moles / volume in litter
Number of moles = Molarity × volume in litter
Number of moles = 0.48 M × 2.50 L
Number of moles = 1.2 mol
Mass of HI:
Number of moles = mass/molar mass
Mass = Number of moles × molar mass
Mass = 1.2 mol × 127.9 g/mol
Mass = 153.48 g
