Explanation:
Given
The enthalpy of formation of RbF (s) is –557.7kJ/mol
The standard enthalpy of formation of RbF (aq, 1 m) is –583.8 kJ/mol
The enthalpy of solution of RbF = Enthalpy of RbF (aq) - Enthalpy of formation of RbF (s)
= -583.8 - (-557.7) kJ/mol
= -26.1 kJ/mol
The enthalpy is negative which means that the temperature will rise when RbF is dissolved.
Answer:
Oxygen
Explanation:
First of all, let's remember that covalent bonds are formed between nonmetal atoms. Given the list of the atoms, calcium is the only metal (it belongs to group 2A, alkaline earth metals). This means calcium doesn't form covalent bonds, it forms ionic bonds. The remaining atoms are all nonmetals and form covalent bonds.
To avoid ambiguity and several choices possible for this problem, we'll assume that we're only talking about diatomic molecules (molecules consisting only of two atoms) in this question.
In covalent bonding, atoms join together to have their valence shells filled, that is, to have octets in their shells (except hydrogen which can only have up to 2 electrons in its shell). Let's look at how many bonds each of these nonmetals will form in a diatomic molecule:
- Chlorine is in group 7A, it has 7 valence electrons, meaning it only needs 1 electron from a covalent bond to have an octet. This implies chlorine will have a single bond.
- Hydrogen is in group 1A, it has 1 valence electron and the maximum it can have in its valence shell is 2 electrons, so it also lacks 1 electron that will be provided by the other atom in a single bond.
- Nitrogen is in group 5A (it has 5 valence electrons). This means it needs 3 more to gain an octet, those would come from a triple bond.
- Carbon is in group 4A (it has 4 valence electrons). It needs 4 more electrons to gain an octet. A quadruple bond would not be possible, the greatest carbon can make is a triple bond in CO having a lone pair remaining on carbon.
- Oxygen is in group 6A (it has 6 valence electrons). It needs 2 more electrons to gain an octet. This implies it would make a double bond to obtain two more electrons from the other atom and acquire an octet.
I think it's 10 but i may not be right so, sorry if it's wrong lol
Answer:
Fossils are the some traces or portions of the animals or plants, buried and preserved from past in rocks, sediments or ice.
Explanation:
Correct match is as follows-
- Mold and cast fossils- An organism is buried in sediment after it dies.The hard part of organism leave behind a empty space imprinted in the rock. Later sediments and minerals fill the space and harden to make the original copy of the organisms.
- Carbon film fossils- An organism buried in sediments gets squeezed and heated inside the earth , leaving behind a thin carbon outline of the organism on a rock.
- Amber fossil- An organism covered in tree resin or tree sap , which then hardens with the body of the organisms preserved inside.
- Ice fossil- An organism dies in a cold place on earth , its body becomes frozen and covered in layers of ice . The hard and soft part of the body may be preserved.
Answer:
c
Explanation:
CI or O
Carla Vista Company has the following information available for September 2020.
Unit selling price of video game consoles $410
Unit variable costs $328
Total fixed costs $36,900
Units sold 600
Compute the unit contribution margin.
Unit contribution margin enter the unit contribution margin
Prepare a CVP income statement that shows both total and per unit amounts.
Compute Carla Vista’ break-even point in units.
Break-even point in units enter Break-even point in units units
Prepare a CVP income statement for the break-even point that shows both total and per unit amounts.
