This is an incomplete question, here is a complete question.
Calculate the solubility of each of the following compounds in moles per liter. Ignore any acid-base properties.
CaCO₃, Ksp = 8.7 × 10⁻⁹
Answer : The solubility of CaCO₃ is, 
Explanation :
As we know that CaCO₃ dissociates to give
ion and
ion.
The solubility equilibrium reaction will be:

The expression for solubility constant for this reaction will be,
![K_{sp}=[Ca^{2+}][CO_3^{2-}]](https://tex.z-dn.net/?f=K_%7Bsp%7D%3D%5BCa%5E%7B2%2B%7D%5D%5BCO_3%5E%7B2-%7D%5D)
Let solubility of CaCO₃ be, 's'




Therefore, the solubility of CaCO₃ is, 
<span>Answer:
H-C-N H-N-C C-H-N
Notice that C-H-N is the same as N-H-C just written backwards. ( i.e. they have the same connectivtiy.) You can exclude the last one with H in the middle since H has two bonds and 4 electrons around it. At this point you couldn't differentiate between the first two, so I would give you the connectivity in such a problem, which in this case is H-C-N.</span>
Answer is: the volume of an irregular object is 4,00 ml.
<span>Volume is the amount of space the object occupies and can be finded immersing it in water in a container with volume markings and than see how much the level of the container changes (goes up).
</span>V(irregular object) = V(final volume) - V(initial volume).
V(irregular object) = 7,50 ml - 3,50 ml.
V(irregular object) = 4,00 ml.
Answer:
THE VOLUME OF THE BALLOON IS 1.45 L
Explanation:
At sea level:
Volume = 2 L
Pressure = 1 atm
Temperature = 12 °C
At 30000 ft altitude:
Pressure = 0.30 atm
Temperature = -55°C
Volume = unknown
Using the general gas formula:
P1 V1 / T1 = P2 V2 / T2
Re-arranging the formula by making V2 the subject of the equation, we have;
V2 = P1 V1 T2 / T1 P2
V2 = 1 * 2 * 12 / 0.30 * 55
V2 = 24 / 16.5
V2 = 1.45 L
The volume of the balloon at the temperature of -55 C and 0.30 atm is 1.45 L