Master Chemistry with Fun Quizzes & Brain Teasers!

10 Baking soda (NaHCO3) decomposes when it is heated according to the equation below. How many kilojoules of heat are required to decompose 1.95molNaHCO3(s)?2NaHCO3(s) + 1290 - Na2CO3(s) + H20(9) + CO2(9)126 13258129 la 2.53 x 107
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Which statements about fossils are true? Check all that apply.They give clues about Earth's climate in the ancient past.Only animals can become fossils.Fossils show what Earth was like millions of years ago.Fossils can be found in ice.The best fossils are preserved in tar.
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A baseball pitcher throws a fastball to a batter.
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A gas at 80 kPa occupies a volume of 5 mL. What volume will the gas occupy at 70 kPa
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Which equation represents a spontaneous reaction?A)Ca + Ba2+ to Ca2+ + BaB)Co + Zn2+ to Co2+ + ZnC)Fe + Mg2+ to Fe2+ + MgD) Mn + Ni2+ to Mn2+ + Ni
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List some common liquids that you think are acidic or basic. For example, do you think orange juice is acid or base? Why do you think each liquid is an acid or base?
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3. A wave has y frequency of 100 Hz and a speed of 50 m/s. What is the wavelength?
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how does a runoff get polluted.
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Which of the following is equal to 0.500 mol?A. 32.0 g O(2)B. 103.6 g PbC. 36.0 g H(2)OD. 14.0 g CO(2)help please
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Why do you think adding water (dilution) changes how acidic or basic the liquid is? Explain your thinking.
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Gravity does NOT * 10 points increase when the distance between two objects increases. increase when the distance between two objects decreases. increase when the mass of one object increases. increase when the mass of both objects increases.
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A scientist wants to know how individual lions within a pride interact with each other in their own environment.To do this, the scientist sedates and tags all of the lions within a pride. Then, he places several remotely-controlled video cameras near the lions' den and performs an observational field study. He collects continuous video footage over the span of one year, analyzes the video, and then forms conclusions based on his observations.This example shows that A. observational field studies are not a valid form of scientific investigation. B. conditions and variables are best controlled in observational field studies. C. there is only one way to acquire scientific knowledge. D. not all scientific knowledge is gained through controlled laboratory experiments.
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how many molecules are there in 125 grams of sugar, C12H22O11
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how many molecules are there in 125 grams of sugar, C12H22O11
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PLEASE HELPWhy do atoms form bonds with other atoms? Provide example using octet rule
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What is the pH of a solution of KOH with a hydroxide concentration of [OH] = 1.10 x 10
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the volume of one mole of a substance is 22.4 L at STP for all what
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A metal, M , of atomic mass 56 amu reacts with chlorine to form a salt that can be represented as MClx. A boiling point elevation experiment is performed to determine the subscript , and therefore, the formula of the salt. A 30.2 g sample of the salt is dissolved in 100.0 g of water and the boiling point of the solution is found to be 376.81 K. Find the formula of the salt. Assume complete dissociation of the salt in solution.CAN SOMEONE PLEASE HELP ME!!! I AM VERY CONFUSED AND ITS DUE TODAY BEFORE 11:55 THANK YOU IN ADVANCED
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Use the drop-down menus to identify the type of mass movement in each image. Grass covered land with a large depressed area. Muddy water is rushing across a roadway.Dirt and fallen trees cover a roadway.
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Which of the following shows the solution set to the quadratic equation 8x2+40x=0
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Equal volume of solutions with pH equal to 4 and pH equal to10 are mixed. pH of the resulting solution is
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what would be considered more dilute? sweet tea or unsweetened tea
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what pressure, in atmospheres is exerted by 0.325 mol of hydrogen gas in a 14.08L container at 35C ?
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The Sl symbol for volume is
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