<h3><u>Answer</u>;</h3>
A. When a reaction is at chemical equilibrium, a change in the system will cause the system to shift in the direction that will balance the change and help the reaction regain chemical equilibrium.
<h3><u>Explanation</u>;</h3>
- Le Chatelier's principle states that when a change or a "stress" is placed on a system that is at equilibrium, the system will shift in such a way to relieve that change or stress.
- The stresses include; changing the concentration of reactants or products, altering the temperature in the system and changing the pressure of the system.
- Therefore; <u><em>when a chemical reaction is at equilibrium and experiences a change in pressure, temperature, or concentration of products or reactants, the equilibrium shifts in the opposite direction to offset the change. </em></u>
Answer:
B. water displacement is used "graduated cylinder is filled with water (100 mL) and the object is then put inside. ... If the new water level is (120 mL) we now know that the object has a volume of 20 mL."
Explanation:
The oxidation number of H is -1.
Sum of the oxidation numbers in each element =
charge of the complex
CaH₂ has 1 Ca atom and 2H atoms. The charge of
the complex is zero. Let’s say Oxidation number of H is "a".
Then,
<span> (+2)
+ 2 x a = 0 </span>
<span> +2 + 2a = 0</span>
2a = -2
a = -1
Hence, the oxidation number of Hydrogen atom in CaH₂ is -1
<u>Answer:</u> The correct option is A) They have fixed energy values.
<u>Explanation:</u>
Electron is one of the sub-atomic particle present around the nucleus of an atom which is negatively charged.
In an atomic model, it is assumed that the electron revolves around the nucleus in discrete orbits having fixed energy levels.
These electrons when jumping from one energy level to another, some amount of radiation is either emitted or absorbed.
These fixed energy levels are given by the Bohr model and thus, the electrons are quantized.
Hence, the correct option is A) They have fixed energy values.
Answer:
1 ) H2O 2) Hydrogen and oxygen 3) Compound
Explanation:
1) To write a chemical formula, you write the number of molecules of an element (2 hydrogen atoms + 1 Oxygen atom, or H2O). The letters represent the element's notation on the periodic table, while the number that follows it represents the number of atoms of that particular element within the compound. If there is no number that follows the letter, there is only one.
2) Letter "H" on the periodic table represents hydrogen, while "O" represents oxygen
3) You can tell that this is a compound because it is made of two or more elements found on the periodic table
