Answer:
C, 42g
Explanation:
In thermal equilibrium, both bodies (metal pellet and water) both have the same final temperature (46.3°C).
Assuming no heat is lost to surroundings,
the energy lost from metal pellet = energy gained for water
Since E = mc∆T
(energy = mass x specific heat capacity x temperature change)
mc∆T (metal pellet) = mc∆T (water)
100 x 0.568 x (116-46.3) = m 4.184 (46.3 - 23.8)
3958.96 = 94.14m
m = 42g
Salt=compound, soda=liquid solution, aluminum foil=element, milk=colloid,
steel=solid solution
The mixture contains:
CaCO3 + (NH4)2CO3 in which the amount of carbonate CO3 = 60.7% by mass
Let, the total mass = 100 grams
Mass of CaCO3 = x grams
Mass of (NH4)2CO3 = y grams
Thus, x + y = 100 ------------(1)
Mass of CO3 = 60.7% = 60.7 g
Molar mass of CO3 = 60 g/mol
Total # moles of CO3 = 60.7 g/60 g.mol-1 = 1.012 moles
The total moles of CO3 comes from CaCO3 and (NH4)2CO3. Therefore,
moles CaCO3 + moles (NH4)2CO3 = 1.012
mass CaCO3/molar mass CaCO3 + mass (NH4)2 CO3/molar mass = 1.012
x/100 + y/96 = 1.012---------(2)
based on equation 1 we can write: y = 100-x
x/100 + (100-x)/96 = 1.012
x = 71.2 g
Mass of CaCO3 = 71.2 g
Answer:
3 atoms
Explanation:
2 hydrogen atoms and 1 oxygen atom
