Answer:a) 0.1 mole. b) 4g. c) 2% d) 196 mL
Explanation: in 200mL , 0.1mole
mw NaOH = 40g/mol —> 4g in 0.1 mole
4g in 200mL so 2g in 100mL
density NaOH = 1g/mL so if 4g in 200 mL, 4mL , 196 mL water
Answer:
Explanation:
A galvanic cell is composed of two electrodes immersed in a suitable electrolyte and connected via a salt bridge. One of the electrodes serves as a cathode where reduction or gain of electrons takes place. The other half cell functions as an anode where oxidation or loss of electrons occurs.
The representation is given by writing the anode on left hand side followed by its ion with its molar concentration. It is followed by a salt bridge. Then the cathodic ion with its molar concentration is written and then the cathode.
As it is given that cadmium acts as anode, it must be on the left hand side and copper must be on right hand side.
The buoyancy of an object is dictated by its density. So let us calculate for density, where:density = mass / volume
Calculate the volume first of a solid cube:volume = (6 cm)^3 = 216 cm^3 = 216 mL
Therefore density is:density = 270 g / 216 mLdensity = 1.25 g / mL
Therefore this object will float in the layer in which the density is more than 1.25 g / mL.
Answer:
B. liquid to gas
Explanation:
Matter exists in 3 different states:
- Solid: in solids, particles in the substance are tightly bond to each other through strong intermolecular forces. Therefore, they can only vibrate around their fixed position, but they cannot move freely: as a result, the distance between the particles is the smallest among the 3 states of matter.
- Liquid: in a liquid, particles are able to slide past each other, however there are still intermolecular forces keeping them not too far from each other. As a result, in liquids, particles are on average more distance from each other compared to solids.
- Gas: in a gas, particles are completely free to move, as the intermolecular forces between them are negligible. As a result, in gases, the distance between molecules is the greatest, compared with solids and liquids.
Therefore, the phase changes in which the average distance between molecules increases is:
B. liquid to gas
Answer:
7 is the mass number of li and 3 is the atomic number
a 3
b 7
c 3
d 4
