A chemical change creates a new substance
Answer:
Metal
Element: Calcium
Valency: 2
Explanation:
To find the element, let's use the periodic table. (Look below)
We already went past 3 shells, just need the 2 electrons after it.
Just skip to the 4th row and count 2 to the right
We end up at Calcium.
Calcium is a metal and we're also on the alkaline earth metals column.
Calcium will need to lose 2 electrons to reach stability, so the valency is 2.
Answer:
Explanation:
Hello,
At first, the answer is wrong, consider the following procedure:
- the pKs, leads to a Ks of:
- now, stating the equilibrium for the calcium sulfate (whereas x is the change during the equilibrium):
- x becomes the concentration of calcium ions and one of the contributions for the total concentration of sulfate ions, thus:
- finally, since the sodium sulfate is totally dissolved, we just simply add its concentration (equal to the sulfate ions yielded by itself) to the outgoing sulfate concentration from the calcium sulfate:
Bibliography:https://books.google.com.co/books?id=LQwyfFc3pXsC&lpg=PA243&ots=zIJN3nSFWE&dq=pKs%20chemistry&pg=PA244#v=onepage&q=pKs%20chemistry&f=false page 243
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Find the number of moles
C = n / V
C(Concentration) = 0.30 moles / L
V ( Volume) = 2 L
n = ??
n = C * V
n = 0.30 mol / L * 2 L
n = 0.60 mol
Find the molar mass
2Na = 23 * 2 = 46 grams
1S = 32 * 1 = 32 grams
O4 = 16 * 4 = 64 grams
Total = 142 grams / mol
Find the mass
n = given mass / molar mass
n = 0.06 mol
molar Mass = 142 grams / mol
given mass = ???
given mass = molar mass * mols
given mass = 142 * 0.6
given mass = 85.2 grams.
85.2 are in a 2 L solution that has a concentration of 0.6 mol/L
Answer:
D. If the distance between the crests of the waves increase, the frequency decreases.
Explanation:
Wavelength is the distance between two successive crests and troughs while frequency is the number of complete cycle per seconds
Velocity = Frequency × wavelength
Frequency and wavelength are inversely proportion