How does the law of conservation of mass apply to this reaction Mg + 2HCl + H2 + MgCl2?
Only the hydrogen needs to be balanced. There are equal numbers of magnesium and chlorine,
The law of conservation of mass has already been applied. There is an equal number of each element on both sides of the
equation
The equation needs to be balanced. There are fewer hydrogen atoms in the equation than magnesium or chlorine,
• Hydrogen and chlorine need to be balanced. There is an equal amount magnesium on each side

9. write the chemical equation for the following word equations. include symbols for physical states in the equation. a. solid zinc sulfide + oxygen gas -> solid zinc oxide + sulfur dioxide gas b. aqueous hydrochloric acid + aqueous barium hydroxide -> aqueous barium chloride + water

Calculate the number of moles of ethane in 100 grams

Which statement correctly describes the phosphate ion, ? it is composed of one phosphorus atom and four oxygen atoms covalently bonded together, and there is a –3 charge distributed over the entire ion. it is composed of one phosphorus atom and four oxygen atoms covalently bonded together, and there is a –3 charge on the phosphorus atom. it is composed of one phosphorus atom and four oxygen atoms ionically bonded together, and there is a –3 charge distributed over the entire ion. it is composed of one phosphorus atom and four oxygen atoms ionically bonded together, and there is a –3 charge on the phosphorus atom.