Answer:
Energy is added (postive enthalpy)
Explanation:
Ice melting means solid turns into liquid. Solid is more stable than liquid thus you must put in energy to weaken the forces of solid and turn it into liquid. Thus, you must put in energy to melt ice. This makes the enthalpy of the system to be positive.
Answer:
The nitrogens are both sp3 hybridized. Their bonds are formed by sp overlaps. The carbon and oxygen are sp2 hybridized. The double bond with oxygen is produced by a sp2 overlap to form the sigma component and a probital overlap to form the pi component. The bonds with hydrogen are formed by sp2 overlaps.
Explanation:
The problem above can be solved using M1V1=M2V2 where M1 is the concentration of the concentrated, V1 is the volume of the concentrated solution, M2 is the concentration of the Dilute Solution, V2 is the Volume of the dilute solution. Hence,
(3.0 M)(V2)=(250 mL)(1.2M)
V2 (3.0)= 300
V2= 100 mL
Therefore, you need 100 mL of 3.0 M HCl to form a 250 mL of 1.2 M HCl.
Probably sodium Na because it has a similar atomic mass and number
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