Answer:
Aluminum, boron, and gallium are likely together in one group because they have the same number of valence electrons, and carbon and germanium are likely together in another group because they have the same number of valence electrons.
Explanation:
The correct answer here is B - when chlorine accepts an electron to
complete its octet and becomes a chlorion ion it becomes an Anion. An
anion is a negatively charged ion. Chloride ions are an important
electrolyte within the body.
So calculate the H for the other two reactions a room temperature and combine the reactions to calculate the H of the decomposition of calcium carbonate using the Hess's Law
Answer: You multiply and divide when rounding division significant figures
Explanation: Both multiplying and dividing significant figures have the same rule. That rule is, the FINAL ANSWER of a multiplication and division problem should be rounded to the number of significant figures that is the least amount of any figures used in the multiplication or division. Let us demonstrate below.
Answer:
pH = 7.233
Explanation:
Initially, the buffer contains 0.208 moles of NaHSO₃ and 0.134 moles of Na₂SO₃.
NaHSO₃ reacts with NaOH thus:
NaHSO₃ + NaOH → Na₂SO₃ + H₂O
50.0 mL of 1.00 M NaOH are:
0.0500L × (1mol / 1L) = 0.0500moles of NaOH added. That means after the addition are produced 0.0500moles of Na₂SO₃ and consumed 0.0500moles of NaHSO₃. That means final moles of the buffer are:
NaHSO₃: 0.208 mol - 0.050 mol = <em>0.158 mol</em>
Na₂SO₃: 0.134 mol + 0.050 mol = <em>0.184 mol</em>
<em> </em>
As pKa of this buffer is 7.167, it is possible to use H-H equation to find pH, thus:
pH = pKa + log₁₀ [Na₂SO₃] / [NaHSO₃]
pH = 7.167 + log₁₀ [0.184] / [0.158]
<em>pH = 7.233</em>
