Answer:
D. Solutions are formed when the water’s polar molecules separate the polar molecules of an ionic or molecular compound.
Explanation:
Solutions are homogeneous mixtures formed by interaction between solutes and solvents.
Water based solutions have water as the solvents and mostly ionic and molecular compounds as their solutes.
Water is a polar solvent that is capable of dissolving many compounds by hydrating them. The molecules of water surrounds the solute and forces them to separate.
Answer:
Consider how the speaker begins the speech, the support given in the body of the speech, and how the speaker concludes. Listen for changes in tone. Listen for how the speaker uses delivery techniques such as pauses, pace, voice, metaphors and symbolism, repetition and parallelism, and vocabulary.
Explanation:
Answer:
All three states of matter (solid, liquid and gas) expand when heated. The atoms themselves do not expand, but the volume they take up does.
When a solid is heated, its atoms vibrate faster about their fixed points. The relative increase in the size of solids when heated is therefore small. Metal railway tracks have small gaps so that when the sun heats them, the tracks expand into these gaps and don’t buckle.
Liquids expand for the same reason, but because the bonds between separate molecules are usually less tight they expand more than solids. This is the principle behind liquid-in-glass thermometers. An increase in temperature results in the expansion of the liquid which means it rises up the glass.
Molecules within gases are further apart and weakly attracted to each other. Heat causes the molecules to move faster, (heat energy is converted to kinetic energy) which means that the volume of a gas increases more than the volume of a solid or liquid.
However, gases that are contained in a fixed volume cannot expand - and so increases in temperature result in increases in pressure.:
Answer:
Substance 4
Explanation:
Density is defined as mass per unit volume. A substance floats in another when its density is less than that of the substance on which it floats.
If an object is immersed in a denser liquid, it will sink
Since the density of water is 1 g/cm^3, any substance whose density is less than that of water will float in it.
If we look at the table, substance 4 has a density of 0.5g/cm^3. Hence, substance 4 is expected to float in water.
