The 4 main one are Iron, oxygen, silicon, and magnesium<span />
Answer:
Physical weathering is caused by purely mechanical changes to the rock, while chemical weathering is caused by chemical reactions.
Explanation:
Chemical weathering happens when the chemicals get diluted and dissolved in water and seep and percolate down the rock surfaces.
Physical weathering happens when rocks are fragmented into minor fragments while ensuring no alterations in their chemical makeup. The main causes behind physical weathering include spontaneous fluctuations in temperature like too high or too low heat or cold
<span>The answer to question 2 is C. A magnifying glass is an example of a plano-convex lens, where one side of the lens is flat and the other is a convex curve. The answer to question 3 is either B or C. A converging lens is curved on both sides and so the rays of light coming out of it converge at a point, which is known as the focal point. When the object is inside the focal point, the image is real and inverted. If it is inside the focal point, the image is virtual and upright. Therefore the image in this question will be upright. The focal length is the distance between the image that is being magnified and the centre of the magnifying lens. A real image can only be formed when the object is further away from the lens than the focal length. Therefore, in this question, the image is virtual, as the object is closer to the lens than the focal length. The answer to question 4 is D because the index of refraction cannot be less than 1. The answer to question 5 is D because only concave mirrors can produce real images; other types produce virtual images. For question 6, the answer is D. In the rainbow, each of the colours refracts at a slightly different angle; red has the smallest refractive index and violet the largest. Of the options, orange is closest to red. For question 12, A is the answer. A higher operating temperature is not a reason fluorescent lamps are better than incandescent lamps because they have a lower operating temperature. Question 15: all of these are characteristics of different electromagetic waves. For question 18, B is true - special care must be taken when low illuminance is required to reduce glare. The answer to question 19 is B - a compound microscope makes use of two lenses. For question 20, the answer is 5 meters away. The illuminance (E) is equal to light intensity (I) divided by the square distance from the light source (d). Therefore, 4 = 100/d squared. To switch this around, d squared is equal to 100/4 = 25. Then find the square root of 25, which is 5.</span>
Answer:
3.329 g
Explanation:
First you need to determine the molar mass of H2S which is 34.1 g/mol.
With that we know that to find the moles of H2S we just divide the mass of sample with the molar mass.
3.54 g / 34.1 g/mol = 0.103812317 mol of H2S
This means that there is also 0.103812317 mol of sulfur since there is 1 mole of sulfur per 1 mole of H2S.
The molar mass of sulfur is 32.065 g/mol and to find the mass of sulfur you need to multiply the molar mass with the moles of the compound.
0.103812317 mol * 32.065 g/mol = 3.329 g of sulfur
Let me know if you get something else or if something is unclear in the comments so that we can figure it out.
Answer:
The number of proton of magnisium = 12
