Answer:
The concentration the student should write down in her lab is 2.2 mol/L
Explanation:
Atomic mass of the elements are:
Na: 22.989 u
S: 32.065 u
O: 15.999 u
Molar mass of sodium thiosulfate, Na2S2O3 = (2*22.989 + 2*32.065 + 3*15.999) g/mol = 158.105 g/mol.
Mass of Na2S2O3 taken = (19.440 - 2.2) g = 17.240 g.
For mole(s) of Na2S2O3 = (mass taken)/(molar mass)
= (17.240 g)/(158.105 g/mol) = 0.1090 mole.
Volume of the solution = 50.29 mL = (50.29 mL)*(1 L)/(1000 mL)
= 0.05029 L.
To find the molar concentration of the sodium thiosulfate solution prepared we use the formula:
= (moles of sodium thiosulfate)/(volume of solution in L)
= (0.1090 mole)/(0.05029 L)
= 2.1674 mol/L
The elements in a periodic table are arranged in the increasing order of their atomic number.
The answer is (1) CaCO3. The bond between C and O is covalent bond. And the bond between Ca2+ and CO3 2- ion is the ionic bond. So the compound CaCO3 satisfy this condition.
Answer:
<em>It is false.</em>
Explanation:
<em>Weathering is the general process by which rocks are broken down at Earth's surface. Erosion is a set of processes that loosen and move soil and rock downhill or downwind. Umm...for example, imagine you are having ice cream in your hand out on a sunny day, if the ice-cream melts and falls down, it is called erosion and if the ice-cream melts but it doesn't fall down, it called weathering. </em>
