Answer:
The element with electron configuration 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^5 is manganese (25Mn).
Explanation:
Step 1: Data given
The element with electron configuration 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^5
has 25 electrons.
This element has 2 electrons on the first shell, 8 electrons on the second shell, 13 electrons on the third shell and 2 electrons on the outer shell (valence electrons).
This means this element is part of group VII.
The element with 25 electrons, we can find on the periodic table, with atomic number 25.
The element with electron configuration 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^5 is manganese (25Mn).
The answer is (2) Copper. Because copper is consist of atom. If it is decomposed, the atom will be changed. While chemical change is just the break down and form of chemical bonds between atoms.
Answer:
Pb2+(aq) + 2Cl–(aq) ----> PbCl2(s)
Explanation:
The net ionic equation shows the main reaction that takes place in a system. Hence, a net ionic equation focusses only on those species that actually participate in the reaction.
For the reaction between Pb(NO3)2 and NH4Cl , the net ionic equation is;
Pb^+(aq) + 2Cl^-(aq) ---> PbCl2(s)
Answer:
molecular formulas of the hydrocarbons
Answer:
components of a nucleotide - DNA and RNA
