we have a total of three times the original number (6.923 * 10**-7) moles of all ions, or 2.077 * 10**-6 moles of ions
<h3>What is aragonite-strontianite solid solution dissolution in nonstoichiometric Sr (HCO3)2 solutions?</h3>
Synthetic strontianite-aragonite solid-solution minerals were dissolved in non-stoichiometric CO2-saturated Sr(HCO3)2 and Ca(HCO3)2 solutions at 25°C. The reactions in Sr(HCO3)2 solutions frequently become incongruent, precipitating a Sr-rich phase before attaining stoichiometric saturation. Mechanical mixes of solids approach stoichiometric saturation in terms of the least stable solid in the combination.
This surficial phase has a thickness of 0-10 atomic layers in Sr(HCO3)2 solutions and a thickness of 0-4 layers in Ca(HCO3)2 solutions and dissolves and/or recrystallizes within 6 minutes of reaction.
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Answer: Chemical change
Explanation:
Physical change is a change in which there is no rearrangement of atoms and thus no new substance is formed. There is only change in physical state of the substance. The change can be reversed using physical methods.
Chemical change is a change in which there is rearrangement of atoms and thus new substance is formed. There may or may not be a change in physical state. The change can only be reversed using chemical methods.
Thus when iron and sulfur are heated in a test tube, the chemical change occurs and thus lead to formation of new substances which could not be separated using magnet.
Answer:
Explanation:
The given reaction equation is:
2A + 4B → C + 3D
We know the mass of compound A in the reaction above. We are to find the mass of compound D.
We simply work from the known mass to calculate the mass of the unkown compound D
Using the mole concept, we can find the unknown mass.
Procedures
- We first find the molar mass of the compound A from the atomic units of the constituent elements.
- We then use the molar mass of A to calculate its number of moles using the expression below:
Number of moles of A = 
- Using the known number of moles of A, we can work out the number of moles of D.
From the balanced equation of the reaction, it is shown that:
2 moles of compound A was used up to produced 3 moles of D
Then 
x number of moles of A would give the number of moles of D
- Now that we know the number of moles of D, we can find its mass using the expression below:
Mass of D = number of moles of D x molar mass of D
