The correct answer is A. The image shows a nuclear fission. This takes place in any of the heavy nuclei after capture of a neutron. This is the opposite of nuclear fusion. In this case, nuclei are broken down into two.
Answer:
Energy is added (postive enthalpy)
Explanation:
Ice melting means solid turns into liquid. Solid is more stable than liquid thus you must put in energy to weaken the forces of solid and turn it into liquid. Thus, you must put in energy to melt ice. This makes the enthalpy of the system to be positive.
Answer:
The shape of the BF3 molecule is best described as trigonal planar.
Explanation:
The Lewis Structure for BF3 is like this:
_ _
| F | | F |
\ /
B
|
| F |
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It forms three angles of 120° each. The bonds are in the same planar that's why it is trigonal planar and they are exactly the same.
Boron and Fluorine have 3 covalent bonds, produced by electronic promotion that enables the 2py and 2pz orbitals, leaving an electron to pair in the 2px. So boron will have 3 possible electrons to pair in 2s1, 2px and 2py, remember that electronic configuration for B is 1s2, 2s2, 2p1
By hybridization between the orbitals 2s2 and 2p1, the electrons of F, can joined to make the covalent bond. The new B configuration is 1s2, 2s1, 2px1, 2py1 (these last three, hybrid orbitals)
Answer:
Independent: The amount of vinegar
Dependent: The dye result on the egg
Controlled: The type of eggs, the size of jars, the dye tablet, how much she stirs, etc.
Explanation:
The independent variable is what is being changed, which in this case, is the amount of vinegar being added to each jar. The dependent variable is what is being measured or observed. Kesha is looking for what happens to the egg when she adds more vinegar with the dye. Lastly, there could be a couple of controlled variables. Like, the dye tablet, the size and brand of the eggs, the types of jars, how long she stirs each egg, and so on. The controlled are just variables kept constant so that any result observed is because of one singular change, the independent variable.
