Q: Q: What kind of a reaction occurs when a substance reacts quickly with oxygen? Read this paragraph and choose the correct option from the provided answers: A combustion reaction occurs when a substance reacts quickly with oxygen (O 2 ). For example, in the Figure below , charcoal is combining with oxygen. Combustion is commonly called burning, and the substance that burns is usually referred to as fuel. The products of a complete combustion reaction include carbon dioxide (CO 2 ) and water vapor (H 2 O). The reaction typically gives off heat and light as well. The general equation for a complete combustion reaction is:. Choices: - invention reaction - Fluid Reaction - nitrogen reaction - combustion reaction A:
A: combustion reaction

Q: Q: Fluoride ion is widely used in water supplies to help prevent what? Read this paragraph and choose the correct option from the provided answers: Fluoride ion is widely used in water supplies to help prevent tooth decay. Chloride is an important component in ion balance in blood. Iodide ion is needed by the thyroid gland to make the hormone thyroxine. Choices: - rust - bacteria - chlorine taste - tooth decay A:
A: tooth decay

Q: Q: In a ketone, two of which kind of groups are attached to the carbonyl carbon atom? Read this paragraph and choose the correct option from the provided answers: Note The carbonyl group is ubiquitous in biological compounds. It is found in carbohydrates, fats, proteins, nucleic acids, hormones, and vitaminsorganic compounds critical to living systems. In a ketone, two carbon groups are attached to the carbonyl carbon atom. The following general formulas, in which R represents an alkyl group and Ar stands for an aryl group, represent ketones. Choices: - ions - nitrogen groups - oxygen groups - carbon groups A:
A: carbon groups

Q: Q: What makes monotremes different than other mammals? Read this paragraph and choose the correct option from the provided answers: 29.6 Mammals Mammals in general are vertebrates that possess hair and mammary glands. The mammalian integument includes various secretory glands, including sebaceous glands, eccrine glands, apocrine glands, and mammary glands. Mammals are synapsids, meaning that they have a single opening in the skull. A key characteristic of synapsids is endothermy rather than the ectothermy seen in other vertebrates. Mammals probably evolved from therapsids in the late Triassic period, as the earliest known mammal fossils are from the early Jurassic period. There are three groups of mammals living today: monotremes, marsupials, and eutherians. Monotremes are unique among mammals as they lay eggs, rather than giving birth to young. Eutherian mammals are sometimes called placental mammals, because all species possess a complex placenta that connects a fetus to the mother, allowing for gas, fluid, and nutrient exchange. Choices: - they lack backbones - they spawn - they reproduce asexually - they lay eggs A:
A: they lay eggs