Answer:
The bromine molecule, Br2 will likely react with Sr in a similar way to chlorine molecule, Cl2.
Explanation:
Chlorine belongs to group 7 of the periodic table. Elements in this group are known as halogens. Its molecule has the formula Cl2. The next element in the group after chlorine is bromine. Its molecule has a formula Br2. It has similar properties as chlorine, therefore, it would react with Strontium in a similar way to chlorine.
Elements belonging to the same group of the periodic the table have similar chemical properties as they contain the same number of valence electrons. Chlorine and Bromine both belong to group 7 of the periodic table and each have seven valence electrons. They both react with metals to form salts even though reaction with chlorine is more vigorous as it is more reactive than bromine. They both form negatively-charged ions with a charge of -1.
Reaction of Strontium with the halogens:
With chlorine: Sr + Cl2 ---> SrCl2
With bromine: Sr + Br2 ---> SrBr2
The salts formed are both crystalline salts with high melting and boiling points.
Atoms. Well, they can be broken down, but that won't happen that fast.
Answer:
1. An apple is something that has matter.
2. Light does not have matter. It neither has mass or takes up and space.
3. Physical changes only change the appearance of a substance, not its chemical composition. Chemical changes cause a substance to change into an entirely substance with a new chemical formula. Chemical changes are also known as chemical reactions.
4. A chemical reaction is usually accompanied by easily observed physical effects, such as the emission of heat and light, the formation of a precipitate, the evolution of gas, or a color change. Absolute confirmation of a chemical change can only be validated by chemical analysis of the products!
5. A precipitate is a solid that forms out of solution.
6. In simple terms, the endothermic reactions absorb energy from the surrounding that is in the form of heat. On the other hand, an exothermic reaction releases energy into the surrounding of the system.
Explanation:
Matter is anything that has mass and takes up volume.
i. The dissolution of PbSO₄ in water entails its ionizing into its constituent ions:
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ii. Given the dissolution of some substance
,
the Ksp, or the solubility product constant, of the preceding equation takes the general form
![K_{sp} = [B]^y [C]^z](https://tex.z-dn.net/?f=K_%7Bsp%7D%20%3D%20%5BB%5D%5Ey%20%5BC%5D%5Ez)
.
The concentrations of pure solids (like substance A) and liquids are excluded from the equilibrium expression.
So, given our dissociation equation in question i., our Ksp expression would be written as:
![K_{sp} = \mathrm{[Pb^{2+}] [SO_4^{2-}]}](https://tex.z-dn.net/?f=K_%7Bsp%7D%20%3D%20%5Cmathrm%7B%5BPb%5E%7B2%2B%7D%5D%20%5BSO_4%5E%7B2-%7D%5D%7D)
.
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iii. Presumably, what we're being asked for here is the <em>molar </em>solubility of PbSO4 (at the standard 25 °C, as Ksp is temperature dependent). We have all the information needed to calculate the molar solubility. Since the Ksp tells us the ratio of equilibrium concentrations of PbSO4 in solution, we can consider either [Pb2+] or [SO4^2-] as equivalent to our molar solubility (since the concentration of either ion is the extent to which solid PbSO4 will dissociate or dissolve in water).
We know that Ksp = [Pb2+][SO4^2-], and we are given the value of the Ksp of for PbSO4 as 1.3 × 10⁻⁸. Since the molar ratio between the two ions are the same, we can use an equivalent variable to represent both:
So, the molar solubility of PbSO4 is 1.1 × 10⁻⁴ mol/L. The answer is given to two significant figures since the Ksp is given to two significant figures.
