Master Chemistry with Fun Quizzes & Brain Teasers!

can someone help me please
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Chlorine has an atomic number of 17. How many protons are inthe nucleus of a chlorine atom?
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Is this correct?If the temperature is below the melting point the substance is a solidIf the temperature is above the boiling point the substance is a gasIf the temperature is in between the boiling and melting points the substances a liquid.
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To change an object from a liquid to a gas _________ must happenmeltingevaporationsublimationcondensation
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Help plz!!!!!!!!!!!!!!!
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Xander claims that since the model of the atom has been changed so many times, that means it is a weak model. Willow claims that the more a model has been examined and adjusted, the stronger it is. Who is correct and why?
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Differences in states of matter are determined byparticle typeparticle arrangement particle color distance between particles
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Jakasia needed to find the volume of a plastic container in L to see if the 170 L ofsolution that she had would fit inside. She knew that one side was 2.5 ft, theheight of the box was 60 cm, and width of the box was 0.8 m. Use dimensionalanalysis to determine if Jakasia's solution will fit in the container.
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The reaction in which methane is burned, CH4 +202 --> 2H20 + CO2, is an example of acombustion reactionO synthesis reactionO decomposition reactionO precipitate reaction
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How could measuring the melting point of a solid help decide whether it was a mixture or a compound?
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The characteristic brightline spectrum of potassium is produced when electrons A) jump to higher energy levels B) return to lower energy levels C) are lost by neutral potassium atoms D) are gained by neutral potassium atoms E) are released from the nucleus
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PRACTICE PROBLEM Two compounds, A and B, have the same molecular formula, C6H8. Both A and B react with two molar equivalents of hydrogen in the presence of platinum to yield cyclohexane. Compound A shows three signals in its broadband decoupled NMR spectrum. Compound B shows only two NMR signals. Compound A shows an absorption maximum at 256 nm, whereas B shows no absorption maximum at wavelengths longer than 200 nm. What are the structures of A and B
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Prior to science lab, Maria had been drinking a can of soda. When she walked into the lab she set it down on the hot plate at her station. She heard a liquid beginning to boil, and realized that the previous students had forgotten to turn off the hotplate and the boiling noise was from the remaining soda in the can. Without thinking, she picked up the can with her bare hands, and put it upside down into the sink which was half full of liquid. Immediately the can crushed as though it was going to be recycled. What do you think is happening to the soda and air in the can? Support you claim in Question 4, by explaining why you think it is happening. Formulate your hypothesis for the problem. Critique Marias laboratory safety procedures.
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Radium decays to form radon. Which equation correctly describes this decay? Superscript 226 Subscript 88 Baseline Upper R a right arrow Superscript 222 Subscript 84 Baseline Upper R n + Superscript 4 Subscript 4 Baseline Upper H e Superscript 226 Subscript 88 Baseline Upper R a right arrow Superscript 222 Subscript 86 Baseline Upper R n + Superscript 0 Subscript negative 1 Baseline e Superscript 226 Subscript 88 Baseline Upper R a right arrow Superscript 222 Subscript 86 Baseline Upper R n + Superscript 0 Subscript + 1 Baseline e Superscript 226 Subscript 88 Baseline Upper R a right arrow Superscript 222 Subscript 86 Baseline Upper R n + Superscript 4 Subscript 2 Baseline Upper H e
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The mercury level in a capillary tube placed in a dish of mercury is actually below the surface of the mercury in the dish. Please choose the answer that best explains the phenomenon.a. Mercury flows freely and is incapable of clinging to the walls of the capillary tube. b. Mercury has an incredibly high density for a liquid, making it too heavy to climb the capillary tube, c. The cohesive forces of mercury are much stronger than its adhesive forces. The adhesive forces may be repulsive, causing the mercury level in the tube to be lower than the mercury in the dish. d. Mercury is a polar molecule. It creates incredibly high cohesive forces, which prevent the mercury from climbing the capillary tube.
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Two students are working together to build two models. Both models will represent the molecular structure of sodium bicarbonate, NaHCO3 commonly known as baking soda. The students are using toothpicks to represent bonds and jelly beans to represent atoms. Red jellybeans represent sodium atoms, white jellybeans represent hydrogen atoms, black jellybeans represent carbon atoms, and blue jelly beans represent sodium atoms, white jellybeans represent hydrogen atoms, like jellybeans our cruise and carbon atoms, and we jellybeans that is an oxygen atoms. Identify the number of each jelly bean needed to make both models.
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Please choose the best description, or definition of Faunal Succession.principle stating that specific groups of organisms lived and died within a specifictime frame due to the ice ageprinciple stating that specific groups of fawns lived in a specific region and arefound in the rocks shoing fawns onl live in specific areas.principle stating that specific layers of the earth have contain fauna of differenttypes showing biodiversity.rinciple stating that specific groups of organisms have followed, or succeeded.one another in a definite sequence through Earth history
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Once upon a time, I was traveling from Kaunas Lithuania to Klaipeda to see Egle, the queen of serpents. Being the queen of serpents, she has certain magical powers. In exchange for some sand, salt, and iron, she will grant my wish. I put all three things in my bottle together and traveled. During my travels, the salt, sand, and iron got mixed up. No big deal right? Wrong. Egle wants each thing separated before she will grant my wish.... Am I just out of luck completely?Please write your response and explain your reasoning.
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Select the reagents you would use to synthesize the compounds below from benzene. Use the minimum number of steps. No more than three steps are required in any synthesis. a. Br2, FeBr3 b. CH3COCi. AICl3 c. SO3, H2SO4 d. Cl2, FeCl3 e. KMnO4, H2O f. HNO3, H2SO4 g. Fe, H3O then OH h. CH3Cl, AICl3 m-chlorobenzenesulfonic acid: 2,4,6-tribromoaniline
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What type of crust type does transform boundary have?
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Please help fill in the blanks: The torso, which houses the apparatus consists of upper and lower cavities that are partitioned by the________.The upper cavity is called the _____ (or colloquially the chest) and is almost totally filled with the heart and lungs; the lower the cavity, the abdomen or belly, contains much of the ____ and other organs and glands.
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Question 51 ptsChloroethene,C2H3C1, reacts with oxygen according to the equation below.2 C2H2Cl (9) + 5O2(g) + 4CO2 (g) + 2 H20 g) + 2 HCl (9)What is the amount, in mol, of H2O produced when 10.0 mol of C2H3Cl and 10.0 mol ofO2 are mixed together, and the above reaction goes to completion?08.0010.004.0020.0Lo
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What happens when you touch two hot bowls made of different materials? The wooden and metal bowl are both at the same temperature and HOTTER than your finger. Compare the direction and speed of the heat arrows for the wooden and metal bowl. Explain WHY and what affects HOW the arrows move from the wooden and metal bowl to the finger.
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THIS IS TIMED!! PLEASE HELP A student has about 250 mL of the liquid acetone. She wants to get a precise and accurate measure of the actual volume of the liquid without losing any. Which of these would be the best instrument to use. 500 mL graduated cylinder (1mL) 100 mL graduated cylinder (0.5mL) 250 mL beaker (5mL) 500 mL beaker (7mL)
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