Answer:
NiS insoluble
Mg₃(PO₄)₂ insoluble
Li₂CO₃ soluble
NH₄Cl soluble
C₁₂H₂₂O₁₁ molecules
Explanation:
<em>Predict whether the following compounds are soluble or insoluble in water.</em>
Based on the solubility rules we can say:
- NiS: Sulfides of transition metals are highly insoluble.
- Mg₃(PO₄)₂: All phosphates (except those with metals of Group 1) are insoluble so Mg₃(PO₄)₂ is insoluble.
- Li₂CO₃: all salts of metals of Group 1 are soluble so Li₂CO₃ is soluble.
- NH₄Cl: all salts of ammonium are soluble so NH₄Cl is soluble.
<em>Which of the following best describes the solute in an aqueous solution of sucrose or C₁₂H₂₂O₁₁(aq)?</em>
Sucrose is a molecular compound in which atoms are linked through covalent bonds. Thus, it does not ionize in water (is a non-electrolyte) and when it dissolves it exists as C₁₂H₂₂O₁₁ molecules.
<u>Answer:</u> When the enthalpy of this overall chemical equation is calculated, the enthalpy of the second intermediate equation is halved and has its sign changed.
<u>Explanation:</u>
Hess’s law of constant heat summation states that the amount of heat absorbed or evolved in a given chemical equation remains the same whether the process occurs in one step or several steps.
According to this law, the chemical equation is treated as ordinary algebraic expressions and can be added or subtracted to yield the required equation. This means that the enthalpy change of the overall reaction is equal to the sum of the enthalpy changes of the intermediate reactions.
The overall chemical reaction follows:
The intermediate balanced chemical reaction are:
(1) 
(2) 
The expression for enthalpy of the reaction follows:
![\Delta H^o_{rxn}=[1\times (\Delta H_1)]+[\frac{1}{2}\times (-\Delta H_2)]](https://tex.z-dn.net/?f=%5CDelta%20H%5Eo_%7Brxn%7D%3D%5B1%5Ctimes%20%28%5CDelta%20H_1%29%5D%2B%5B%5Cfrac%7B1%7D%7B2%7D%5Ctimes%20%28-%5CDelta%20H_2%29%5D)
Hence, when the enthalpy of this overall chemical equation is calculated, the enthalpy of the second intermediate equation is halved and has its sign changed.
Answer:
arteries carry blood from the heart to the lungs and veins carry blood from the lungs to the heart
Explanation:
Arteries carry oxygenated blood from the heart, while veins carry oxygen-depleted blood back to the heart. ... The pulmonary veins transport oxygenated blood back to the heart from the lungs, while the pulmonary arteries move deoxygenated blood from the heart to the lungs.)
Number of proton K=19
so, 42 - 19 =23
then the answer in 19 protons and 23 neutrons
