<span>The half-life of Carbon 14 and radionuclides are used to estimate the absolute (versus relative) age of pre-history items </span>
Answer:
The options <u>(A) -</u>The rate law for a given reaction can be determined from a knowledge of the rate-determining step in that reaction's mechanism. and <u>(C) </u>-The rate laws of bimolecular elementary reactions are second order overall ,<u>is true.</u>
Explanation:
(A) -The rate law can only be calculated from the reaction's slowest or rate-determining phase, according to the first sentence.
(B) -The second statement is not entirely right, since we cannot evaluate an accurate rate law by simply looking at the net equation. It must be decided by experimentation.
(C) -Since there are two reactants, the third statement is correct: most bimolecular reactions are second order overall.
(D)-The fourth argument is incorrect. We must track the rates of and elementary phase that is following the reaction in order to determine the rate.
<u>Therefore , the first and third statement is true.</u>
Answer: C) Non-metals can share pairs of electrons and form covalent bonds
Explanation: The principal reason why it is non-metals that can form covalent bonds is because of their electronegativities. Electronegativity is the tendency of an atom to attract electrons towards itself.
The participating atoms in a covalent bond have to be able to hold the shared electron in place & it is this attraction towards the centre of each participating atom that holds the electrons in place. Metals aren't electronegative, they don't attract electrons towards each other, they'd rather even push the electrons away from themselves (electropositive) to be stable. The closest concept of metals to shared electrons is in metallic bonding, where metals push and donate their valence electrons to an electron cloud which is free to move around the bulk of the metallic structure. But this is nowhere near the type of bonding that exist in covalent bonds.
Intercourse between two beings, usually male and female to procreate.
Answer:
there are 20 oxygen atoms in 4.00 moles of Dinitrogen pentoxide
Explanation:
there are 2 atoms in an oxygen molecule , so each oxygen molecules has at least 2. Dinitrogen pentoxide is N2O5, which has 7 atoms, 2 nitrogen and 5 oxygen. 1 molecule of N2O5 has 5 oxygen atoms, so 4 of then would be 20
