Answer:
b) 2.0 mol
Explanation:
Given data:
Number of moles of Ca needed = ?
Number of moles of water present = 4.0 mol
Solution:
Chemical equation:
Ca + 2H₂O → Ca(OH)₂ + H₂
now we will compare the moles of Ca and H₂O .
H₂O : Ca
2 : 1
4.0 : 1/2×4.0 = 2.0 mol
Thus, 2 moles of Ca are needed.
Answer:
3 years
Explanation:
Given data:
Initial amount of sample = 160 Kg
Amount left after 12 years = 10 Kg
Half life = ?
Solution:
at time zero = 160 Kg
1st half life = 160/2 = 80 kg
2nd half life = 80/2 = 40 kg
3rd half life = 40 / 2 = 20 kg
4th half life = 20 / 2 = 10 kg
Half life:
HL = elapsed time / half life
12 years / 4 = 3 years
Your answer is $20,480.
Hope this Helped!
<h3>Also here is the explanation: </h3><h3>https://www.symbolab.com/solver/equation-calculator/x%3D32000%5Cleft(.8%5Cright)%5E%7B2%7D</h3>
Answer:
The Correct increasing order of solubility is O2 < Br2 < LiCl < Methanol (CH3OH)
Explanation:
Solubility of compounds or molecules are solely dependent on its inter molecular forces or bonding present in them.
Molecules with Hydrogen bonding usually very soluble in water. Ionic compounds are also very soluble in water because they form ions in solutions. Molecules that possess van der waal forces are usually insoluble in water because they are non-polar.
- O2 (oxygen gas) and Br2 (bromine gas) have van der waal forces in them. Van der waal forces are stronger in Br2 (bromine gas) than O2 (oxygen gas) because Br2 has more number of electrons.
- LiCl is ionic in nature which makes it dissolve in water readily. it easily forms its ions (Li+ and Cl- ) in solutions.
- Methanol (CH3OH) has the highest solubility in water compared to LiCl, Br2 and O2 because it contains Hydrogen bonding which is strongest of all inter molecular forces.
Answer:
una ma parra quen est a qui 23^5(-8)
Explanation:
