Answer:
C4H6 + 2HBr = C4H8Br2
Explanation:
Alkynes are organic molecules made of the functional group carbon-carbon triple bonds and are written in the empirical formula of CnH2n−2. They are unsaturated hydrocarbons.
Furthermore, Halogenation reaction of any alkyne such as but-2-yne with any of the hydro halogenated compounds such as HBr, HCl, HF or HI will give an alkane that will have the same number of carbon atoms in the starting material and in the final product.
Halogenation reaction is a reaction that occurs when one or more halogens are added to a substance. Halogens is the seventh column in the periodic table and it include fluorine, chlorine, bromine, iodine, and astatine.

As depth increases, the density of the layers decreases.
The standard state formation reaction is a chemical reaction in which one moles of substance in its standard state is formed from its constituent element in their standard state.All the substance must be in their most stable state at 100kpa and 25 degrees celsius.
therefore for HF is
1/2H2 +1/2F2 =HF
The answer to both is D. Here's why:
For the first, whenever motion changes in a magnetic field, it causes electrons to move. Electricity, which is needed to power a lightbulb, is just a term for movement of these electrons. Electrons aren't created, they're always there in the wire. It's just that the permanent magnet gets them to move, which produces electricity.
For the second, it is very similar to the first. A magnet won't cause any electric current at rest, it always requires motion in order to produce an electric current. If you keep both of those in mind, it should help in the future. Hope this helps!
Molarity is defined as the number of moles of solute in 1 L of solution
the mass of Ca(NO₃)₂ present - 8.50 g
therefore number of moles of Ca(NO₃)₂ - 8.50 g / 164 g/mol = 0.0518 mol
the volume of solution prepared is 755 mL
therefore if there are 0.0518 mol in 755 mL
then in 1000 mL the number of moles - 0.0518 mol / 0.755 L
molarity is therefore - 0.0686 M