7. Which of the following will be the result of compound if Hydrogen gas and orygen gas combine? A Hydrogen peroxide B. Salt C. Sugar D. Water 8. What elements made up the compound Carbon Dioxide? A Carban and Carbon A innot B Carbon and Oxide C. Carbon and Oxygen D. Carbon and Hydrogen 9. Which of the following is correctly matched? 1. Nitrogen: Element: Nitrous Oxide: Compound Leon: Element Rust: Compound I. Mercury: Element: Copper: Compound IV. Oxygea: Element: Water: Compound A L. II, III, IV B. I, I, I only C. I, II, IV only D. I and II only​