Hello Gary!
*Sorry if I'm late*
Your answer is going to be 65.
Element A (which is actually Zinc) has the atomic number of 65. (I remember having got memorize this also).
Pretty much the explanation is that the number of patrons is equivalent to the element's atomic number!
Hope this helps!
Have a nice day :D
Avogardo's number is a constant, named after the scientist Amedeo Avogadro that represents the number of molecules or atoms that are contained in the amount of substance given by one mole.<span> Na= 6.022×10</span><span>23
Mole on the other hand is </span> a chemical mass unit,defined to be 6.022 x 1023 molecules<span>, </span>atoms, or some other unit. This is the reason why t<span>he mole and Avogadro’s number are now almost synonymous with each other. </span>
Explanation:
As the given reaction is as follows.
So, according to the balanced equation, it can be seen that rate of formation of will be twice the rate of disappearance of
.
And, it is known that rate of disappearance of reactant will be negative and rate of formation of products will be positive value.
This means that,
Rate of the reaction = -Rate of disappearance of
=
=
= M/s
Therefore, calculate the rate of formation of as follows.
Rate of formation of =
= M/s
Thus, we can conclude that the rate of formation of is M/s.
Answer:
is an aqueous reactant
is a liquid product
is a gaseous product
Explanation:
⇔
Hydrogen carbonate dissocates to form carbon dioxide and water. The acid (hydrogen carbonate) is in aqueous form and it dissociates to water (liquid) and carbon dioxide (a gas). It is also seen that the hydrogen carbonate is on the reactant side and it dissociates to produce water and carbon dioxide.
W<u> is an aqueous reactant</u> (a reactant undergoes changes in a chemical reaction
<u /><u> is a liquid product</u> (product refers to the species produced from chemical reaction)
<u /><u> is a gaseous product</u>
Answer : The enthalpy change of dissolution of is -54.0 kJ/mole
Explanation :
where,
q = heat released by the solution
c = specific heat of water =
m = mass of solution = mass of water + mass of = 102.00 + 1.69 = 103.69 g
= change in temperature =
Now put all the given values in the above formula, we get:
Now we have to calculate the enthalpy change of dissolution of
where,
= enthalpy change of dissolution = ?
q = heat released = 0.659 kJ
m = mass of = 1.69 g
Molar mass of = 138.55 g/mol
Therefore, the enthalpy change of dissolution of is -54.0 kJ/mole