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Why did Neil Armstrong go to the moon?

Tension between the United States and Russia influenced President Kennedy to issue an order to NASA to beat the Russians to the moon. Armstrong was one of three crew members on board the flight, which took 102 hours and 45 minutes. Buzz Aldrin and Armstrong spent a little over 21 hours on the lunar surface gathering samples and taking photographs in the Sea of Tranquility.

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What is the real color of blood?

The idea that oxygenated blood is red and deoxygenated blood is blue is a common misconception. In fact, human blood is never blue. It does change color depending on the level of oxygenation. In the arteries, where blood is fully oxygenated, it appears bright red, while in the veins, where the oxygen is depleted, it is a dark red.\nBlood derives its red color from hemoglobin, a reddish iron-containing protein that is found in red blood cells. Hemoglobin bonds with oxygen molecules in the alveoli of the lungs. The heart pumps oxygenated blood through a branching system of arteries until it reac..

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What are colligative properties?

Colligative properties depend on the number of particles found in the solute and on the solvent in a solution. Unlike other chemical properties, colligative properties do not depend on the identity of the solute or of the solvent. Few properties of a solution can be termed as colligative properties, but the vapor pressure depression, boiling point elevation, freezing point depression and osmotic pressure are all examples of colligative properties.\nThe vapor pressure depression is defined as the change in vapor pressure of a solvent that occurs when a new solute is added to said solvent. This ..

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What are four types of pyroclastic materials?

Lava blocks are large rock pieces that are ejected from a volcano. They are solid and angular shaped, with some as large as a car in size. Lapilli are small, pea-sized ejections that all types of lava produce. Floating rock occurs when pumice, another type of pyroclasic material, becomes buoyant. It is able to float for thousands of miles. It is also found on shores near the site of the volcanic eruption.

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How does a pressure transmitter work?

Pressure transducers are used during electronic fetal monitoring to convert data about the body's contractions and the baby's responsive heart rates onto a graph. They are also used in scuba diving to read, convert and transmit information from a scuba diver's pressure tank to a watch-like device worn on the wrist.

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What is a bacterial cell?

Bacterial cells may be gram positive or gram negative. Both types of bacterial cells have cell walls, but these have different compositions. Gram positive bacterial cells contain thick peptidoglycan walls that contain high concentrations of peptides. Gram negative bacterial walls contain thin peptidoglycan walls and exhibit enzymes that help them with mobility. Gram negative bacteria also contain lipid A, which is an endotoxin that can protect the bacterial cell.

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What is the common name for magnesium hydroxide?

Patented in 1818, milk of magnesia was sold for medicinal use as an antacid and laxative. It is also used in antiperspirant products and as a topical treatment for canker sores. Magnesium hydroxide has a molar mass of 58.31 grams per mole. It can be manufactured through a reaction of a solution of magnesium salts and a solution of ammonium hydroxide. It is found naturally in some minerals, such as chlorite.

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How does an ammeter work?

Hans Christian Orsted first discovered the effects of a magnet on a compass. He found that when an electric current was flowing near the compass, its needle would be deflected from pointing north. This original tool that the ammeter was developed from, a multiplier, was used to measure currents. However, it worked only when it was aligned with Earth's natural magnetic field. This was not practical in modern times for measuring electric currents, so an ammeter, which relies on an electromagnetic current running perpendicularly through a conductor, is used today to measure electric currents..

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What elements make up the sun?

A process called nuclear fusion makes the sun burn hot. During this process, hydrogen is converted to helium. Because of nuclear fusion, each day, there is less hydrogen in the sun and more helium. Eventually, the sun will run out of hydrogen to process, and scientists believe that in around 5 million years, it will use all of its hydrogen and begin to die. During its death, the sun will start to cool and become less bright.

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What does pH measure?

A pH of 7 means that a substance is neutral, so it is neither an acid nor a base. A reading of less than 7 means that the substance is acidic, whereas a measurement of greater than 7 means that the substance is basic. The more extreme the reading is, the more acidic or basic a solution is. For example, a substance that triggers a reading of 1 on the pH scale is extremely acidic. On the other hand, if a chemical has a pH of 14, it is a very strong base.

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