30 because it is the highest number of marriage
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:
Increasing the temperature will cause chemical changes to occur faster. Decreasing the temperature, causes the particles to lose energy which causes them to move around less and slower. The less they move, the less collisions occur, and the less reactions occur between the chemicals = slower reaction rate.
Explanation:
Porque la temperatura de la agua es neutral
ANSWER:
London dispersion and hydrogen bonds.
EXPLANATION :
Every molecule experiences London dispersion as an intermolecular force.since the ammonia ion has hydrogen atoms bonded to nitrogen,a very electronegative atom,the molecule is also polar since the nitrogen atom more strongly pulls on the electrons from the hydrogen atoms than the hydrogens themselves do.
This effect is similar to that water,where the oxygen pulls the electrons of the hydrogen atoms with a greater magnitude,resulting in the oxygen having a partial negative charge and the hydrogens having a partial positive charge relative to each other.
This polarity shows that the molecule has dipole-dipole intermolecular forces but since the polarity is from a result of highly electronegative atoms (such as nitrogen,oxygen,fluorine) and hydrogen atoms actually bonded to them,the polarity is categorized in it's own intermolecular force called a hydrogen bond.
I HOPE IT HELPS:)
