Lara is studying the quality of water from natural resources. She knows that surface water is more prone to pollution. Which of the following is a source of surface water pollution?

Which symbol is used to represent a reversible reaction?

Tina is studying climate change. She learns that reducing methane emissions is important. What is a major source of methane emissions from human activities?

Which acid is present in vinegar?

Which of the following is an acidic oxide?

Omar is studying marasmus. He learns that marasmus is characterized by emaciation. What is emaciation?

Vera is studying chemical equilibrium. She learns that a closed system is essential. What is a closed system?

Khalid is learning about the preparation of alkanes by the reduction of alkyl halides. He uses 2-bromobutane (C4H9Br) and reduces it. What alkane is formed?

Rania is studying photosynthesis. She understands that photosynthesis is a natural carbon sink. Which organisms are primarily responsible for photosynthesis?

Emma is conducting an experiment to determine the density of a metal. She measures the mass and volume. What is the formula for density?

Which gas is present in the highest percentage in the atmosphere?

Yusuf is studying ways to deal with water pollution. He knows that proper waste disposal is important. What is a proper way to dispose of household chemicals?

Uma is learning about the concept of acids and bases. She knows that according to the Arrhenius concept, acids produce H+ ions in water. Which of the following is an Arrhenius acid?

Lara is recording the color change of an indicator in an acid-base titration. She notes the color at the endpoint. What type of data is this?

Hina is studying reversible reactions. She learns that not all reactions are reversible. Which of the following is an example of a reaction that is reversible?

Chloe is studying the Bronsted-Lowry concept. She knows that an acid is a proton donor and a base is a proton acceptor. In the reaction: HCl + H2O → H3O+ + Cl-, what is the acid?

Which method is used to remove permanent hardness?

Which of the following is a fossil fuel?

Julia is learning about phosphates in water. She knows that phosphates from fertilizers and detergents can enter water bodies. What is a disadvantage of phosphates in water?

Removal of products shifts equilibrium toward:

Vera is studying haloalkanes. She learns that haloalkanes are alkanes with halogen atoms. Which of the following is a haloalkane?

Alkanes are hydrocarbons having:

Nitrogen oxides are mainly released from:

Nadia is studying closed chain compounds. She learns that closed chain compounds contain rings. Which of the following is a closed chain compound?

Laura is learning about the deficiency of carbohydrates. She understands that a lack of carbohydrates can lead to fatigue. What is a good source of complex carbohydrates?

Julia is studying the properties of alkanes. She knows that alkanes are less dense than water. Which of the following alkanes is used as a solvent?

Which class of compounds contains only carbon and hydrogen?

Which disease is caused by deficiency of vitamin B1?

Yusuf is learning about alkalis. He knows that alkalis are soluble bases that release OH- ions in water. Which of the following is not an alkali?

Ibrahim is studying human activities that cause air pollution. He learns that agriculture contributes to air pollution. Which gas is released from agricultural activities?