Answer 1
The sample will dissolve in more than 1 minute.
Explanation :-
Generally Solubility and rate of solubility of substances increase with the increase in temperature. So lower the temperature less fast will it dissolve in the same amount of water.
Since at 50 C it takes 1 minute to dissolve, at 20 C which is lower temperature it will take more time to dissolve.
Answer 2
Transition metals
Explanation:-
Hardness depends on the extent of metallic bonding for metals. More the number of electrons more the metallic bonding.
Alkali metals with just 1 valence electron have weak metallic bonding. Alkaline earth metals have just 2 valence electrons. Transition elements has more electrons in penultimate shell and valence shell than lanthanides. Transition metals with most metallic bonding are the hardest
Answer:
The pressure inside the container is 6.7 atm
Explanation:
We have the ideal gas equation: P x V = n x R x T
whereas, P (pressure, atm), V (volume, L), n (mole, mol), R (ideal gas constant, 0.082), T (temperature, Kelvin)
Since the container is evacuated and then sealed, the volume of the body of gas is the volume of the container.
So we can calculate the pressure by
P = n x R x T / V
where as,
n = 41.1 g / 44 g/mol = 0.934 mol
Hence P = 0.934 x 0.082 x 298 / 3.4 L = 6.7 atm
Answer:
The number of carbon atoms is twice the number of magnesium atoms
False, it’s not mechanical energy it’s thermal energy.
