See the correct answer is b.)PbS
Answer:
Coefficient
Explanation:
Chemical equation:
aA + bB → dD
This equation shows that reaction is balanced by coefficient q,b and d.
Reactant coefficients Product Coefficient
A a D d
B b
Every balanced equation follow the law of conservation of mass.
Law of conservation of mass:
According to the law of conservation mass, mass can neither be created nor destroyed in a chemical equation.
Explanation:
This law was given by french chemist Antoine Lavoisier in 1789. According to this law mass of reactant and mass of product must be equal, because masses are not created or destroyed in a chemical reaction.
For example:
In given photosynthesis reaction:
6CO₂ + 6H₂O + energy → C₆H₁₂O₆ + 6O₂
there are six carbon atoms, eighteen oxygen atoms and twelve hydrogen atoms on the both side of equation so this reaction followed the law of conservation of mass. The numbers 6 with CO₂, 6 with H₂O and 6 with O₂ are coefficient which balance the equation.
Answer:
Explanation:
Oxidation:
Oxidation involve the removal of electrons and oxidation state of atom of an element is increased.
Reduction:
Reduction involve the gain of electron and oxidation number is decreased.
Oxidizing agents:
Oxidizing agents oxidize the other elements and itself gets reduced.
Reducing agents:
Reducing agents reduced the other element are it self gets oxidized.
Consider the following reaction:
2AgCl + Zn → 2Ag + ZnCl₂
In this reaction oxidation state of Zn on left side is 0 while on right side +2 so it gets oxidized and oxidation state of Ag on left side is +1 and on right side 0 so it get reduced.
4NH₃ + 3O₂ → 2N₂ + 6H₂O
In this reaction oxidation state of nitrogen on left side is -3 while on right side 0 so it gets oxidized and oxidation state of oxygen on left side is 0 and on right side -2 so it get reduced.
Fe₂O₃ + 2Al → Al₂O₃ + 2Fe
In this reaction oxidation state of iron on left side is +3 while on right side 0 so it gets reduced and oxidation state of Al on left side is 0 and on right side +3 so it get oxidized.
Answer:
The piece of wood will sink
Explanation:
If an object has a density higher than water, it will sink, and the piece of wood is more dense than water when measured.
The physical method that can be used for obtaining a sample of salt from a small beaker of salt and water would be evaporation.
<h3>Separation of salt and water</h3>
A mixture of salt and water can be separated by a method known as evaporation. This is based on the assumption that the salt in question is a water-soluble salt.
In order to separate the salt/water mixture:
- Place the mixture in a suitable evaporating dish
- Boil the mixture until all the water evaporates.
- The remaining residue would be the salt
Care should be taken not to overheat the residue in order to avoid melting. Evaporation is generally used to separate a mixture of water and soluble salt. If the salt is insoluble, filtration using a suitable filter paper will filter off the salt while the water is collected as the filtrate.
More on evaporation can be found here: brainly.com/question/1097783
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Which physical method can be used for obtaining a sample of salt from a small beaker of salt water?
