A scientist adds heat to each of the following substances. Which will probably absorb the most heat before its temperature chang
es significantly? 50 g of solid copper 50 g of solid iron 50 g of liquid water 50 g of sand Question 2(Multiple Choice Worth 2 points) A drop of water placed on a smooth, dry surface will form a dome-shaped droplet instead of flowing outward in different directions. Which of these best explains this observation? The bonds between hydrogen and oxygen atoms are very strong. The electrons in the atoms attract the electrons in the other atoms. Water molecules at the surface experience fewer hydrogen bonds than water molecules within the liquid. Water molecules near the surface produce more buoyant force than water molecules within the liquid.
Question 3(Multiple Choice Worth 2 points) Which of these best explains what happens when the ionic substance calcium chloride (CaCl2) dissolves in water? The oxygen atoms in the water molecules are attracted to the Ca2+ ions. The oxygen atoms in the water molecules are attracted to the Cl− ions. The hydrogen atoms in the water molecules are attracted to the Ca2+ ions. The oxygen atoms in the water molecules are attracted to the H+ ions.
Question 4(Multiple Choice Worth 2 points) Which of these statements about water is true? Its atoms share electrons equally. It can dissolve all known substances. Its molecules are farther apart in the solid state than in the liquid state. It has a lower specific heat than nearly all known metals.
A scientist adds heat to each of the following substances. Which will probably absorb the most heat before its temperature changes significantly?
50 g of liquid water
A scientist discovers a new substance. The molecules of the substance form hydrogen bonds with each other. When the molecules lose a lot of energy, the hydrogen bonds hold them relatively far apart. Based on this information, what can the scientist infer about the substance?
It expands when it freezes.╖
Which of these best explains why a paper clip can float on water?
Water molecules near the surface produce more buoyant force than water molecules within the liquid.
Which of these best explains why the hydrogen atoms in a water molecule are attracted to Cl− ions in sodium chloride (NaCl)?
Acceleration is the name we give to any process where the velocity changes. Since velocity is a speed and a direction, there are only two ways for you to accelerate: change your speed or change your direction—or change both.
