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#Examples of physical changes series

Some changes in cognition are normal with age, such as slower reaction times and reduced problem-solving abilities.

Short-term memory shows noticeable changes with age, but long-term memory declines less with age.

Older adults are capable of learning new skills even late in life, though learning may take longer than for younger adults.

For most older adults, age-associated changes in cognition (thinking) are mild and do not significantly interfere with daily functioning.

has increased by 70 percent in the last 20 years, from 2.7 million to 4.6 million. The population of older immigrants in the U.S. Older Latinos will account for the largest increase: In 2030, they will constitute 22 percent of the older population, compared to 8 percent of today’s older adults.

Between 20, the White population 65+ is projected to increase by 59 percent, compared with 160 percent for older minorities.

Whereas today, most older adults are White, a dramatic transformation will occur within the next two decades, resulting in a population that is more culturally diverse.

However, as this age group includes five decades of individuals, the differences among older adults are great - actually greater than those seen in other age groups. If you eat galactose molecules, they need to be converted into glucose before your body can use them.Many assume that older adults are all alike. For example, your body uses glucose as an energy source. Specificity means the molecules will only work in specific reactions, not all of them. Scientists say that the arrangement of atoms allows for a high degree of specificity, especially in the molecules of living things. Isomers have atoms bonded in different orders.Įach of the sugars goes through different chemical reactions because of the differences in their molecular structure. Even though they are made of the same atoms, they have very different shapes and are called isomers. The sugars glucose, galactose, and fructose all have six carbon atoms, twelve hydrogen atoms, and six oxygen atoms (C 6H 12O 6). The resulting compounds might have the same number of atoms, but they will have a different structure or combination of atoms.

#Examples of physical changes series

Some chemical changes are extremely small and happen over a series of steps. Rusty pipes in abandoned buildings are real world examples of the oxidation process. The molecules change their structure as the iron is oxidized, eventually becoming iron oxide (Fe 2O 3). You can watch the process happen over a long period of time. Iron (Fe) rusts when it is exposed to oxygen gas in the air. The oxygen in the air reacts with the sugar and the chemical bonds are broken. Fire activates a chemical reaction between sugar and oxygen. Burning a sugar cube is a chemical change. Melting a sugar cube is a physical change because the substance is still sugar. Those bubbles are evidence of the chemical changes. In this example, you may see bubbles of oxygen (O 2) gas.

However, behind the scenes, billions of chemical bonds are being created and destroyed. The chemical change as hydrogen peroxide (H 2O 2) becomes water cannot be seen since both liquids are clear. While some experiments show obvious chemical changes, such as a color change, most chemical changes are not visible. The water molecules are still water molecules.Ĭhemical changes happen on a much smaller scale. No chemical changes took place when you melted the ice. Physical actions, such as changing temperature or pressure, can cause physical changes. You added enough energy to create a phase change from solid to liquid. When you melt an ice cube (H 2O), you have a physical change because you add energy. No chemical bonds were created or broken. Also, since this was a physical change, the molecules in the can are still the same molecules.

It wasn't a change in the state of matter because the energy in the can did not change. However, you only changed the shape of the can.

When you step on a can and crush it, you have forced a physical change. Chemical changes happen when atomic bonds are broken or created during chemical reactions. Chemical changes happen on a molecular level when you have two or more molecules that interact. Physical changes are usually about physical states of matter. Some changes are obvious, but there are some basic ideas you should know. It is important to understand the difference between chemical and physical changes.