Answer:
-12162.47 joules (or -12000 joules when accounting for significant figures)
Explanation (btw I used 1 cal as 4.184 joules because SI units are better):
q = m c delta T
q = (70.9) (4.184) (25 - 66)
q = (70.9) (4.184) (-41)
q = -12162.47 joules
Given :
Mass of oxygen containing carbon monoxide (CO) is 2.666 gram .
To Find :
How many grams of carbon (C) would be present in carbon monoxide (CO) that contains 2.666 grams of oxygen (O) .
Solution :
By law of constant composition , a given chemical compound always contains its component elements in fixed ratio (by mass) and does not depend on its source and method of preparation.
So , volume of solution does not matter .
Moles of oxygen ,
.
Now , molecule of CO contains 1 mole of C .
So , moles of C is also 0.167 mole .
Mass of carbon ,
.
Therefore , mass of carbon is 2 grams .
Hence , this is the required solution .
I think it’s A but I’m not sure, if it’s wrong I’m sorry
Answer: The concentration of hydrogen ions for this solution is
.
Explanation:
Given: pOH = 11.30
The relation between pH and pOH is as follows.
pH + pOH = 14
pH + 11.30 = 14
pH = 14 - 11.30
= 2.7
Also, pH is the negative logarithm of concentration of hydrogen ions.
![pH = - log [H^{+}]](https://tex.z-dn.net/?f=pH%20%3D%20-%20log%20%5BH%5E%7B%2B%7D%5D)
Substitute the values into above formula as follows.
![pH = -log [H^{+}]\\2.7 = -log [H^{+}]\\conc. of H^{+} = 1.99 \times 10^{-3}](https://tex.z-dn.net/?f=pH%20%3D%20-log%20%5BH%5E%7B%2B%7D%5D%5C%5C2.7%20%3D%20-log%20%5BH%5E%7B%2B%7D%5D%5C%5Cconc.%20of%20H%5E%7B%2B%7D%20%3D%201.99%20%5Ctimes%2010%5E%7B-3%7D)
Thus, we can conclude that the concentration of hydrogen ions for this solution is
.
Answer:
All are having different valent cation and anion like mono,di and trivalent polyatomic ions .
A. RbNO3
B. K2S
C. NaHS
D. Mg3(PO4)2 formed by divalent Mg+2 and trivalent PO43-
E. CaHPO4
F. PbCO3 , lead is in Pb+2 form
G. SnF2
H. (NH4)2SO4
I. AgClO4
J. BCl3