Answer:
C-18
Explanation:
Step one follow order of operations
Add and subtract from left to right(-5)+(7)=2-(-4)+(12)
STEP 2
Apply negative Rule -(-4)=+4=2+4+(12)
then add 2+4+12=18
Oxygen has 8 protons and 10 electrons due to the addition of 2 electrons, determined from the ion charge. Likewise an ion of potassium has 19 protons and 18 electrons. Charge on fluorine would be -1 and charge on calcium would be +2. Atomic number is the same as the number of protons, so it would be 6, the mass number is the sum of protons and neutrons which would be 13, and the charge is 0, as it is an atom and not an ion.
If completely dissociates in water, it means it is a dilute strong base.
<h3>What is a base?</h3>
A base is a substance that can neutralize the acid by reacting with hydrogen ions.
An acid is a substance that donates hydrogen ions and a base is a substance that accepts hydrogen ions.
Ca(OH)₂ does not have hydrogen ions to donate, but it can accept hydrogen ions to form H₂O according to this equation:
H⁺ + OH⁻ → H₂O.
Hence, Ca(OH)₂ is a base.
A strong base is a base that dissociates completely into metallic and hydroxide ions in aqueous solutions, while a weak base dissociates partially.
Hence, Ca(OH)₂ is a strong base.
Dilute refers to a solution meaning that the substance is not pure and the concentration is low. Since the solution the Ca(OH)₂ is 0.02 M means that it is diluted.
Therefore, we have found that the description of 0.02 M Ca(OH)₂ is a dilute strong base.
Learn more about the base here:
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Answer:
the freezeng point of solution is -12°c b/c it dencity is 0.854 formula =