The density of marble is between 2.6 and 2.8 grams per cm³ .
Density doesn't depend on how much mass or volume of it you have.
The density of a chip of it is the same as the density of a truckload of it.
The answer should be 2KI(aq)+Hg(NO3)2(aq) = 2KNO3(aq) + HgI2(s). This is a double replacement reaction, the valence of elements will not change. The HgI2 is not soluble in water.
If you increase the frequency, the photon will have more energy and can therefore transfer more electrons to the other side. As such, you will have an increased current.
Answer:
0.056moles HF and 0.70M
Explanation:
When a strong acid is added to a buffer, the acid reacts with the conjugate base.
In the system, NaF and HF, weak acid is HF and conjugate base is NaF. The reaction of NaF with HCl (Strong acid) is:
NaF + HCl → HF + NaCl
Initial moles of NaF and HF in 60.0mL of solution are:
NaF:
0.0600L × (0.80mol / L)= 0.048 moles NaF
HF:
0.0600L × (0.80mol / L)= 0.048 moles HF
Then, the added moles of HCl are:
0.0200L × (0.40mol / L) = 0.008 moles HCl.
Thus, after the reaction, moles of HF produced are 0.008 moles + the initial 0.048moles of HF, moles of HF are:
<em>0.056moles HF</em>
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In 20.0mL + 60.0mL = 80.0mL = 0.0800L, molarity of HF is:
0.056mol HF / 0.0800L = <em>0.70M</em>