I would say that the density increases because the distance between the molecules decreases, and therefore becomes smaller, and vice versa the density increases, and that is a physical change not a chemical change.
Answer:
Option A = sodium and bromine
Explanation:
Sodium is metal while bromine is non metal. The bond formed between them is ionic.
Ionic bond:
Ionic bond is formed by the complete transfer of electron form metal to non metal.
Sodium is belongs to the group one while bromine is present in group seventeen. The number of valance electron of bromine are seven. Bromine require one electron to complete the octet, while sodium lose its one valance electron to gain noble gas stable electronic configuration. Thus sodium transfer its electron to bromine and gain positive charge and bromine gain its electron and form negative ion. The forces present between them are electrostatic forces which are very strong.
Na⁺Br⁻
The molar mass or As is 74.9g. Start with 281g multiply by (1mol/74.9g) = 3.75 mols
Put what you don’t want on the bottom (in this case grams) so they the u it’s cancel (if you multiply by grams and the divide by grams they cancel. Ultimately leave what you want on the top ( This case mols) then do the math
Answer:
d. Epoxy
Explanation:
Adhesion or adhesive properties of a substance is the property that allows bonding of dissimilar materials if necessary. Adhesives may have high cohesive strength or a low cohesive strength.
PVC "glue" is usually a solvent for plastic components and these are different type of PVC glues. They function well on plastics.
HDPE - is known as High-density polyethylene or polyethylene high-density is a thermoplastic polymer in short it is what we know as plastic bags or nylon produced from the monomer ethylene. HDPE is not an adhesive
UHMWPE - is known as Ultra-high-molecular-weight polyethylene (UHMWPE, UHMW) is a subset of the thermoplastic polyethylene. Also known as high-modulus polyethylene, (HMPE). UHMWPE is not an adhesive.
An epoxy adhesive is a copolymer adhesive formed by mixing together a resin and a hardener. There are some special epoxies however don't require a hardener, but are activated by heat instead. Others epoxies hardening strength may degrade in under exposure to ultraviolet light or high heat. Adhesives such as epoxies have many different uses. Epoxy may be used on metal, glass, plastic, rubber, fiberglass and fiberglass-reinforced plastic (FRP).
Bakelite or polyoxybenzylmethylenglycolanhydride isn't an adhesive and it was the first plastic made from synthetic components.
Epoxy however has very strong adhesive properties because of the varieties of substances it can bring to together.
An unsaturated hydrocarbon with a double bond is called an alkene. hope i helped.
:)