Answer:
Tests for gases
Hydrogen, oxygen, carbon dioxide, ammonia and chlorine can be identified using different tests.
Hydrogen. A lighted wooden splint makes a popping sound in a test tube of hydrogen.
Oxygen. A glowing wooden splint relights in a test tube of oxygen.
hope it will help
Answer: Option (5) is the correct answer.
Explanation:
It is known that the ground state electronic configuration of silicon is
.
And, we know that when an atom tends to gain an electron then it acquires a negative charge and when an atom tends to lose an electron then it acquires a positive charge.
As
has a +4 charge which means that it has lost 4 electrons. Hence, the electronic configuration of
is
.
According to the Aufbau principle, in the ground state of an atom or ion the electrons fill atomic orbitals of the lowest energy levels first, before filling the higher energy levels.
As 2p orbital is filled after the filling of 2s orbital.
Therefore, we can conclude that 2p orbital will be occupied by the electrons of highest energy for the
ground-state ion.
Answer:
3.052 × 10^24 particles
Explanation:
To get the number of particles (nA) in a substance, we multiply the number of moles of the substance by Avogadro's number (6.02 × 10^23)
The mass of Li2O given in this question is as follows: 151grams.
To convert this mass value to moles, we use;
moles = mass/molar mass
Molar mass of Li2O = 6.9(2) + 16
= 13.8 + 16
= 29.8g/mol
Mole = 151/29.8g
mole = 5.07moles
number of particles (nA) of Li2O = 5.07 × 6.02 × 10^23
= 30.52 × 10^23
= 3.052 × 10^24 particles.
X it by the molar mass of tungsten