Answer:
option C= patterns
Explanation:
The periodic table is helpful to identify the element readily. All the elements are arranged properly. The elements with same physical and chemical properties are placed in same group and period. Periodic table is also helpful to predict the properties of those elements which are not discovered yet. This table is also very helpful to balance the chemical equations. The horizontal rows are called periods while vertical column are called groups. There are seven periods and eighteen groups are in periodic table.
Trends in periodic table:
As we move left to right in a period the atomic radius is decreases with increase of atomic number. The ionization energy goes to increases from left to right in period because of greater hold of nuclear charge on valance electron, so that's way more energy is required to overcome this charge and to make the atom ionic.
From left to right in period electron affinity and electronegativity also increases.
As we move top to bottom in group ionization energy decreases with increase of atomic number because of large atomic radius. The valance electron require less energy to move free. The electron affinity and electronegativity also decreases from top to bottom.
Answer:
Describe how a sample of copper chloride crystals could be made from copper carbonate and dilute hydrochloric acid. Add excess copper carbonate to hydrochloric acid in a beaker, stirring until there is no further reaction. Filter the mixture to remove the remaining copper carbonate, then heat the remaining solution to the point of crystallisation.
Explanation: Hope this is right.
Quarks are present in protons and neutrons, but not electrons; electrons are an elementary particle and thus cannot be broken down any further.
Answer: The sum of the coefficients needed to balance the combustion reaction of methane is 6.
Explanation:
Combustion is a chemical reaction in which hydrocarbons are burnt in the presence of oxygen to give carbon dioxide and water.
According to the law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side. Thus chemical equations are balanced.
The chemical equation for combustion of methane will be :
![CH_4+2O_2\rightarrow CO_2+2H_2O](https://tex.z-dn.net/?f=CH_4%2B2O_2%5Crightarrow%20CO_2%2B2H_2O)
The coefficient foer methane is 1 , 2 for oxygen , 1 for carbon dioxide and 2 for water. The sum is 6.