Answer:
The atomic number on the Periodic Table identifies the number of protons in any atom of that element. Copper, atomic number 29, has 29 protons. Finding the atomic number of an element reveals the number of protons.
To find the number of neutrons in the atom, subtract the atomic number from the atomic mass.
Answer:
The precipitate was chromium hydroxide, which then reacted with more hydroxide to produce a soluble complex, Cr(OH)4
Explanation:
The following reaction takes place when chromium(III) nitrate reacts with NaOH:
+3 NaOH → 
(s)+ 
The precipitate that is formed is chromium hydroxide,
When more NaOH is added, the precipitate reacts with it which then results in the formation of a soluble complex ion:
(s) + 
(aq) → 
(aq)
is soluble complex ion
It showed that the nucleus is positively charged, and that the atom isn't just made of electrons.
The element is TELLURIUM. Tellurium has atomic number 52 with the electronic configuration of [Kr] 4d10 5s2 5p4. The element belongs to group 16 elements on the periodic table. It exhibits various oxidation states: +2, +4, +6, and -2. +4 is its most common oxidation state.
Answer:
The correct answer to the question is
The standard heat of reaction for the reaction is
a. 216.8 kJ released per mole
Explanation:
The heat of reaction is given by [Heat of formation of products] - [Heat of formation of reactants]
In the question we have, heat of formation of the products Zn+2 (aq) = -152.4 kJ/mole and the heat of formation of the reactants = 64.4 kJ/mole
Therefore, the heat of formation of the reaction = (-152-64.4) kJ/mole or
-216.8 kJ/mole released
