Ques: Q: What are ionic substances completely held together by? Read this paragraph and choose the correct option from the provided answers: Ionic substances are completely held together by ionic bonds. The full charges of the ions (for example, Na + and Cl - in sodium chloride) cause electrostatic interactions that result in a stable crystal lattice. We saw in the previous chapter that most ionic compounds have high melting points, are brittle, are often soluble in water, and conduct electricity when melted or dissolved in water. Ionic compounds exist as extended, orderly arrangements of ions. As we will see, this is quite different from the structure of molecular substances, which take the form of collections of individual molecules. The atoms within a molecule are held very strongly together, but the interactions between different molecules are significantly weaker. Choices: - thermal bonds - localized bonds - magnetic bonds - ionic bonds A:
Ans: ionic bonds

Ques: Q: Consisting of a stigma, style, and ovary, the pistil of a flower is what type of organ? Read this paragraph and choose the correct option from the provided answers: The female reproductive organ in a flower is the pistil . It consists of a stigma, style, and ovary. The stigma is the top of the pistil. It is sticky to help it "catch" pollen. The style connects the stigma to the ovary. The ovary is where eggs form and seeds develop. As seeds develop, the ovary turns into a fruit . The fruit protects the seeds. It also attracts animals that may eat the fruit and help disperse the seeds. Choices: - female neural organ - female immune organ - female respiratory organ - female reproductive organ A:
Ans: female reproductive organ

Ques: Q: What is the name of the process in which solid food waste is passed out of the body? Read this paragraph and choose the correct option from the provided answers: Some substances in food cannot be broken down into nutrients. They remain behind in the digestive system after the nutrients are absorbed. Any substances in food that cannot be digested and absorbed pass out of the body as solid waste. The process of passing solid food waste out of the body is called elimination. Choices: - extinction - evaporation - regurgitation - elimination A:
Ans: elimination

Ques: Q: Where is the potential energy of a river the highest at? Read this paragraph and choose the correct option from the provided answers: Electrical circuits are often modeled by using water in a river. The potential energy of the water is the highest at the source of the river and decreases as the water flows down the river toward the end. When the water reaches the ocean, its potential energy has become zero. The circuit shown below has a similar situation. The current in this circuit is drawn in the direction of the electron flow. It starts at the battery on the left, where electrons leave the negative terminal and travel around the circuit. Since all of the current travels across each resistor, these resistors are said to be in series . A series circuit is one in which all of the current must pass through every resistor in the circuit. Returning to the water analogy, there is only one riverbed from the top of the mountain to the ocean. Choices: - the middle - the ocean - the bank - the source A:
Ans:
the source