Answer:
0.025g
Explanation:
Firstly, we need to write a balanced chemical equation.
Ca + 2H2O —-> Ca(OH)2 + H2
From the chemical equation, we can see that one mole of calcium metal yielded one mole of hydrogen gas.
Now, we need to know the actual number of moles of hydrogen gas given off.
The number of moles is the mass divided by the atomic mass. The atomic mass of calcium is 40g/mol. The number of moles is thus 0.5/40 = 0.0125 mole
Since the mole ratio is 1:1, the number of moles of hydrogen gas produced too is 0.0125 moles.
We now Proceed to get the mass of the hydrogen gas produced. This is the number of moles of hydrogen multiplied by the molar mass of the diatomic hydrogen gas. The molar mass of the diatomic hydrogen gas is 2g/mol.
The amount given off is thus 2 * 0.0125 = 0.025g
Answer:
gravity
Explanation: its a force that pulls you down but you are never making contact with it
Answer:
D) constructive
Explanation:
Deposition is a constructive force since it involves dumping sediment in a particular location.
Answer:
it can allow more room for additional living things in the habitat
Explanation:
Use water for an example.
- Taking water can destroy a fish habitat.
- Using excess water can cause water to run out.
- Taking/using water leaves less amounts for others/organisms.
Taking water does not allow additional room for organisms in a habitat.
Answer:
PF3 has a trigonal pyramidal molecular geometry.
Explanation:
PF3 has four regions of electron density / electron clouds around the central P atom. The regions of electrons make a tetrahedral arrangement with a bond angle of 109.5°. Only three regions of electrons are bonding and one is non-bonding, so the overall shape is trigonal pyramidal.
