Answer:
C. A Spring Scale
Explanation:
Using process of elimination, we can quickly decide that a stopwatch and a ruler will not be useful in measuring the force. This leaves us with either the spring scale or a balance scale. A balance scale is used to compare two weights, so this is eliminated. That leaves us with a spring scale. This is because we can attached the spring scale to the car and when we let it go, we can record the force. I hope this helps!
THE EXTRACTION OF METALS FROM THEIR RESPECTIVE ORES IS KNOWN AS METALLURGY.
THE DIFFERENT PROCESS ARE :- ROASTING, CALCINATION, FROTH FLOTATION AND MGNETIC SEPARATION.
Answer:
1. a)
2. a)
3. b)
4. d)
Explanation:
The disposal method is how we throw away the wastes. In a chemical lab, the correct disposal method guarantees the security of the environment and the humans and animals that may be in contact with the materials.
So:
1. Excess chemical: Because it can be toxic, it may be disposed of in the appropriate waste container, which will depend on the characteristics of the material;
2. Reaction mixture: As the excess chemical, it can be toxic, so it must be disposed of at an appropriate waste container;
3. Used filter paper: Generally, the solids in the filter paper is not toxic, so it can be thrown away in the trash can;
4. Cracked or chipped beaker: Because the beaker is made of glass, it can cut when broken, so it must go to a broken glass box, that will protect the people that will deal with it.
Solution is homogeneous mixture which is made up of two or more substances.Solution is composed of solute and a solvent.Solute is the substance that dissolve while solvent is a liquid in which solvent dissolve. Solution involve a chemical change since new substance are formed and involve chemical reaction.
Answer: The boron atom of 
has three hybrid orbitals
Explanation: Hybridization of the molecule can be calculated by:
.....(1)
where,
V = number of valence electrons in the central metal atom
H = number of monovalent atoms
C = cationic charge
A = anionic charge
Here, electronic configuration of B = 
Number of valence electrons = 3
Number of monovalent atoms = 3
Cationic charge = 0
Anionic charge = 0
Putting these values in equation 1, we get
As the Hybridization is 3, which means that boron has 3 hybrid orbitals.
