Memory Mixtures and Soil MemoryVersión en línea Match the vocabulary word to the definition. por Michael Porter A mixture of water, air, tiny pieces of rock, and humus weathering silt soil The smallest particles of rock that make up soil The largest particles of rock that make up soil physical property A characteristic of matter that you can observe or measure directly mixture a combination of two or more different substances that keep their identities the remains of decayed plants or animals in the soil Particles of rock that are smaller than sand but larger than clay topsoil humus The breaking down of rocks on Earth’s surface into smaller pieces decay The upper layer of soil in which plants have most of their roots clay To be slowly broken down by the natural processes that destroy a plant or body sand