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1.)​CaCO3→CO2​+CaO
A scientist heats 30 grams of calcium carbonate (CaCO3) in the chemical reaction shown. What is the total mass of the products?(1 point)
A.)10 grams
B.)15 grams
C.)60 grams <<<<
D.)30 grams

2.)Fe+O2→Fe2O3​
What happens to atoms of Fe and O2 during the reaction?(1 point)
A.)They are lost.
B.)They are rearranged.<<<<
C.)They maintain their properties.
D.)They gain mass.

3.)What is most likely to occur during a chemical reaction?(1 point)
A.)New atoms are created.
B.)Mass is conserved.<<<<
C.)The original substance maintains its properties.
D.)Molecules of the original substance are lost.

{4.}NaHCO3+HC2H3O2→NaC2H3O2+H2O+CO2
A student mixes baking soda (NaHCO3) and acetic acid (HC2H3O2) to produce a chemical reaction shown. Which statement about the reaction is correct?(1 point)
A.)Atoms of Na are destroyed during the reaction.
B.)Some atoms gain mass after the reaction.
C.)There are more H atoms after the reaction.
D.)The atoms of the reactants are regrouped during the reaction.<<<<

{5.}2H2+O2→2H2O
There are four atoms of hydrogen (H) before the reaction. How many atoms of hydrogen are present after the reaction?
(1 point)
A.)8
B.)2
C.)5
D.)4<<<<

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  1. 1. Nope. You start with 30 g CaCO3. You can't get more total products than you started with.
    2. OK
    3. OK. But why didn't you use this in answering 1.
    4. OK
    5. OK

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    DrBob222
  2. I thought you had to add more since he only heated up 30

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  3. and thank you

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  4. Add more what?
    CaCO3 ==> CaO + CO2
    We can calculate grams CaO and grams CO2 produced from 30 g CaCO3, which I will do, but that isn't needed if you remember that the Law of Conservation of Mass says that matter is not created nor destroyed. So if you start with 20 grams CaCO3 you must end up with a total of 30 grams on the other side. mass CO2 + mass CaO = 30 g. But we can prove that's correct by calculating the mass of each and adding them together.
    mols CaO = grams/molar mass = 30/100 = 0.3 mols CaCO3
    We get 0.3 mol CO2 and 0.3 mol CaO.
    grams CO2 = mols x molar mass = 0.3 x 44 = 13.2 g
    grams CaO = mols x molar mass = 0.3 x 56 = 16.8 g
    g CaO + g CO2 = 16.8 + 13.2 = 30.0
    Voila!

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    DrBob222
  5. oops. I made a typo. If you start with 30 grams CaCO3 you must end up with 30 grams of products. Now I see your reasoning. You're thinking that 30 grams CaCO3 will give you 30 g CO2 and 30 g CaO to make a total of 60 grams but it doesn't work that way. You can see from my calculations how much CO2 and how much CaO are produced. The bottom line is the Law of Conservation of mass. Sorry about the typo. My eye sight isn't that good.

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    DrBob222
  6. As I can see here your saying that it is 'C, A, D, B, D' based on some new rearrangements.

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  7. anonymous is right but 1 is 30 grams not 60

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  8. the last question is 4 not 2 but i’m not very smort and anonymous are right otherwise

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  9. The answers to the Chemical Reactions quiz are:
    1. 30 grams
    2. They are rearranged
    3. Mass is conserved
    4. The Atoms of the reactants are regrouped during the reaction
    5. 4
    Hope I could help:)

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  10. trust me is correct make sure to read the answer they might be wrong

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  11. Trust me is right

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  12. @Trustme is right
    Thank you

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  13. Thx Trustme!!!

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  14. trust me is correct plz trust them u will get 100

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  15. Trustme is right!

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  16. STOP CHEATING

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  17. Karen chill,all we are doing is
    1.checking
    or
    2.borrowing answers

    KAREN!!!

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  18. 1. 30 grams
    2. They are rearranged
    3. Mass is conserved
    4. The Atoms of the reactants are regrouped during the reaction
    5. 4
    If you every need me always say #Lost also spread love not hate!
    LoL karen does needs to chill

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  19. Dr.Bob shut up dude

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  20. that girl and i don't cheat, if you don't cheat then why are you here and how do you know about this website. Also we are here because our answer need checked or we need to borrow one if we got some wrong so before accusing us of cheating make sure you have all the facts. Your welcome ;)

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  21. @Trust Me is correct <333

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  22. Anonymous is right I got a 100%😁😁✔️✔️✔️✔️ Thank you

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  23. anonymous is correct except 1 is 30grams

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  24. trust me is correct!! thank youuu <33

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  25. Trust me is correct thanks man/ woman

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  26. trust me is right thank you !

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  27. its
    c
    b
    a
    a
    a

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  28. number 1 was rong i was 30

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  29. Anonymous your rong on 1 it is 30

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  30. Thank you!

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  31. Thanks DrBob 100%, ganna get more later]

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  32. um yes thank u but number one is wrong the answer is 30 not 60

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  33. @TrustMe

    GI Joe approves your message

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  34. trust me tyyy

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  35. thanks trust me

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  36. trust me is 100 percent correct

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  37. @trust me is 100% correct ty

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  38. #lost I love you

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  39. I don't cheat if u don't cheat why you here😎

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  40. cheating? Me? neverrrrr besties. But just because- @lost and @trust or correct 😏

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  41. The lack of trust I have now ✋🏽😭

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  42. somewhat helpful!

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  43. Here are the correct answers 1 is c 2 is c not a 3 is c not d 4 is also c not b 5 is a

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  44. 1.30 grams
    2.they are rearranged
    3.mass is conserved
    4.The atoms of the reactants are regrouped during the reaction.
    5.4
    don't listen to Anonymous, I did and I got a 3/5 on my test.

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  45. Answers:
    D
    B
    D
    C
    A

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  46. Cheating is cool 😎😎😎

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  47. @trustme is right!

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  48. Thank you so much, @trustme, you are 100% correct 😀

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  49. 90% of people marry there 7th grade love. since u have read this, u will be told good news tonight. if u don't pass this on nine comments your worst week starts now this isn't fake. apparently if u copy and paste this on ten comments in the next ten minutes you will have the best day of your life tomorrow. you will either get kissed or asked out in the next 53 minutes someone will say i love u

    Anonymous
    Nov 3, 2021

    Naaaaaaaaaaaaaaaaaaaa Bro

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  50. @Trust Me:) I'm checking answers now...

    100% Thanks ;)

    @I don't cheat

    "StOp cHeaTiNG"

    Bro how did you end up here?!?!
    Plus some just check so get your facts checked. :P
    Some people are smarter than you so deal with it.
    #NO MORE BLASPHEMETH!!!!!

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  51. Ty!! I came to check my answers, and I could've gotten 2/5 if it weren't for @Trust Me:)

    Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm! Tysm!

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  52. i have an apple

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  53. I have a pen

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  54. trust me is right ty:)

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  55. Chemical changes affect the chemical structure of a substance.

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  56. wasd

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