Answer:
C. Hair dryer
Explanation:
Alternating Current
The other kind of electricity is called alternating current, or AC. Power plants produce this
type of electricity. It is carried by large power lines from the plant to your home. When you
plug a TV, a lamp, or a hair dryer into the wall socket, you are using this type of electricity.
Because only those with logic (problem solving capabilities) go to chemistry.
Its Iron and Potassium because if you look at the periodic table,and you go down the list of metals, you can see what metals are there.
1. The Hertzsprung-Russell diagram below shows how the brightness, surface temperature, and color of stars are related.stars would be
A. Barnard’s Star is less bright than the sun, has a surface temperature below 3,800 K, and is red.
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2. The Milky Way galaxy is described as a disk of stars orbiting a central point on the disk. Which of these best explains why people on Earth cannot see the entire shape of the Milky Way?
A. Earth is a part of this galaxy.
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3. A student learns that the sun is classified as a medium-size star and that many stars are much bigger and brighter. However, the student observes that other stars look very dim, even through a telescope.Why do other stars look much dimmer than the sun?
D. As light from other stars travels through space, it gets reflected.
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4. The sun is a mid-sized, main sequence star. What stage is next in the life cycle of the sun?
A. red giant
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5. In November 2013 an object orbiting the sun seemed to disappear behind the sun. When a satellite did not detect the object, astronomers thought that the object had been destroyed when it passed close to the sun. However, when another satellite detected a small, bright object with a fan-shaped tail, astronomers proposed that the object was not destroyed.What type of object were astronomers most likely observing?
A. A comet
Answer:
1.70
Explanation:
The molar mass of perchloric acid is 100.46 g/mol. The moles corresponding to 484 mg (0.484 g) are:
0.484 g × (1 mol/100.46 g) = 4.82 × 10⁻³ mol
4.82 × 10⁻³ moles are dissolved in 240 mL (0.240 L) of solution. The molar concentration of perchloric acid is:
4.82 × 10⁻³ mol/0.240 L = 0.0201 M
Perchloric acid is a strong monoprotic acid, that is, it dissociates completely, so [H⁺] = 0.0201 M.
The pH is:
pH = -log [H⁺] = -log 0.0201 = 1.70
