There are 0.5 moles of NaCl present in a 29.22g sample.
to find moles of a compound you would look at the periodic table to find the mass. in this case, the mass of NaCl is 58.44 g/mol. now, you divide the sample mass of 29.22g by 58.44 g/mol. the grams will cancel each other out and you’re left with 0.5 mol in that sample
hope this helps!
Answer:
2ErF3 +3Mg = 3MgF2 + 2Er
Explanation:
This is a single replacement equation where there are 2 metals. The bonds are broken and new bonds are formed again by Mg and F.
Er has a +3 charge and F has a -1 charge. You switch it around and you get ErF3. Then you add the second reactant, Mg. The product is MgF as stated, and Mg has a charge of +2 and F has -1. You switch it again and you get MgF2. Then the second product Er is there.
Now we have
ErF3+Mg=MgF2+Er
So we balance the equation because of the law of conservation of mass.
Make F equal, so we add the coefficents 2 and 3
2ErF3+Mg=3MgF2+Er
And now Mg and Er need balancing so
2ErF3+3Mg=3MgF2+2Er
Hope this helped
Answer:
Cl^- <S^2-<Sc^3+ <Ca^2+<K^+
Explanation:
We know that ionic radius of ions decreases from right to left in the periodic table. This is because, ionic radii decreases with increase in nuclear charge. This explains why; Sc^3+ <Ca^2+<K^+.
Secondly, even though Cl^- is isoelectronic with S^2-, the size of the nuclear charge in Cl^- is larger compared to that of S^2- . Hence Cl^- is smaller than S^2- in ionic radius owing to increased nuclear attraction in Cl^-.
Answer:
The correct answer is B).
Explanation:
The factors that accelerate a chemical reaction are:
- Temperature: at a higher temperature, the speed of a reaction is increased.
- Pressure: the higher this is, the greater the collisions between molecules and an acceleration of the reaction speed will occur.
-Catalysts: correspond to substances that accelerate chemical reactions, an example are enzymes. There are catalysts that increase the reaction rate and others that generate the opposite effect (they are inhibitors).
There are also other factors that accelerate a chemical reaction such as the concentration of reagents.
First convert the kg to g ----- 0.03kg = 30g
Then divide the mass by the volume ----- 30g ÷ 25mL = 1.2
The density is 1.2g/mL<span />
