Answer:
A: A boulder that is falling after being pushed off a cliff.
C: A pebble in a slingshot before it has been shot.
Explanation:
These are examples of potential energy because they are holding energy before it is released.
Hope this helps
Answer:C
(CH3CH2CH2)2CuLi
Explanation:
The reaction between acyl halides and Grignard reagents or acyl halides and organolithium compounds does not form ketones because the reagents ( Grignard reagent and organo lithium compounds) are too reactive hence the ketone intermediate reacts further to form tertiary alcohols hence the ketone cannot be isolated.
Answer:
Heat change is -14,175 joules, Exothermic
Explanation:
We are given;
- Mass of aluminium bar as 350.0 g
- initial temperature as 70.0 °C
- Final temperature as 25 °C
We are required to determine the heat change and indicate whether endothermic or exothermic;
We know that;
Heat change = Mass of a substance × specific heat × change in temperature
In this case;
Mass of Aluminium = 350.0 g
Change in temperature = (25 - 70)
= -45° C
Specific heat of aluminium = 0.90 J/g°C
Therefore;
Heat change = 350.0 g × 0.90 J/g°C × -45°C
=-14,175 joules
The heat change is exothermic because it is a negative value, also because cooling process involves heat loss and thus an exothermic reaction.
Answer:
pH = 3.513
Explanation:
Hello there!
In this case, since this titration is carried out via the following neutralization reaction:
We can see the 1:1 mole ratio of the acid to the base and also to the resulting acidic salt as it comes from the strong HCl and the weak hydroxylamine. Thus, we first compute the required volume of HCl as shown below:
Now, we can see that the moles of acid, base and acidic salt are all:
And therefore the concentration of the salt at the equivalence point is:
![[HONH_3^+Cl^-]=\frac{0.0044mol}{0.022L+0.0293L} =0.0858M](https://tex.z-dn.net/?f=%5BHONH_3%5E%2BCl%5E-%5D%3D%5Cfrac%7B0.0044mol%7D%7B0.022L%2B0.0293L%7D%20%3D0.0858M)
Next, for the calculation of the pH, we need to write the ionization of the weak part of the salt as it is able to form some hydroxylamine as it is the weak base:
Whereas the equilibrium expression is:
![Ka=\frac{[H_3O^+][HONH_2]}{[HONH_3^+]}](https://tex.z-dn.net/?f=Ka%3D%5Cfrac%7B%5BH_3O%5E%2B%5D%5BHONH_2%5D%7D%7B%5BHONH_3%5E%2B%5D%7D)
Whereas Ka is computed by considering Kw and Kb of hydroxylamine:
So we can write:
And neglect the x on bottom to obtain:
And since x=[H3O+] we obtain the following pH:
Regards!
Answer:
C. Lose three electrons to have a full outer shell
Explanation:
Al is in Group 13 of the Periodic Table, so it has three valence electrons.
It must either lose three electrons or gain five to achieve a stable octet.
It is easier to lose three electrons than it is to gain five, so Al loses three electrons.
D. is wrong, for the same reason.
A. is wrong. If Al lost three electrons, it would be breaking into a stable inner shell.
C. is wrong. Al is a metal, so it will lose electrons in a reaction.
