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Leya [2.2K]
3 years ago
14

When did the mass extinctions happen

Chemistry
1 answer:
Alisiya [41]3 years ago
4 0
Out of the five major mass extinction, one is Cretaceous-Tertiary extinction (K-T extinction). It happened 66 million years ago marked by the end of the Cretinous period.
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CH4 + O2 → CO2 + H2O
Scilla [17]

Answer:

9.8 × 10²⁴ molecules H₂O

General Formulas and Concepts:

<u>Atomic Structure</u>

  • Reading a Periodic Table
  • Moles
  • Avogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.

<u>Organic</u>

  • Naming carbons

<u>Stoichiometry</u>

  • Analyzing reaction rxn
  • Using Dimensional Analysis

Explanation:

<u>Step 1: Define</u>

[RxN - Unbalanced] CH₄ + O₂ → CO₂ + H₂O

[RxN - Balanced] CH₄ + 2O₂ → CO₂ + 2H₂O

[Given] 130 g CH₄

<u>Step 2: Identify Conversions</u>

Avogadro's Number

[RxN] 1 mol CH₄ → 2 mol H₂O

[PT] Molar Mass of C: 12.01 g/mol

[PT] Molar Mass of H: 1.01 g/mol

Molar Mass of CH₄: 12.01 + 4(1.01) = 16.05 g/mol

<u>Step 3: Stoichiometry</u>

  1. [DA] Set up conversion:                                                                                   \displaystyle 130 \ g \ CH_4(\frac{1 \ mol \ CH_4}{16.05 \ g \ CH_4})(\frac{2 \ mol \ H_2O}{1 \ mol \ CH_4})(\frac{6.022 \cdot 10^{23} \ molecules \ H_2O}{1 \ mol \ H_2O})
  2. [DA] Divide/Multiply [Cancel out units]:                                                           \displaystyle 9.75526 \cdot 10^{24} \ molecules \ H_2O

<u>Step 4: Check</u>

<em>Follow sig fig rules and round. We are given 2 sig figs.</em>

9.75526 × 10²⁴ molecules H₂O ≈ 9.8 × 10²⁴ molecules H₂O

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3 years ago
What do scientists call a smart guess?
Alexus [3.1K]
An educated guess is called estimation
4 0
3 years ago
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I am giving brainly to the fastest
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North Dakota and Michigan because it has to be 32 Farenhieht or less to snow
6 0
2 years ago
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A gas has a volume of 3L at 200 kPa. What will its volume be if the pressure is changed to 500 kPa?
marta [7]

Answer:

6L

Explanation:

<em>if it's 3L per 200kPa</em>

then it would be;

4L per 300kPa

5L per 400kPa

6L per 500kPa

that's how i'd work it out in my head, hope it helps, but not sure though!

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Write a report on waves
Bad White [126]

Answer:

The epic emotional journey of a suburban African American family as they navigate love, forgiveness and coming together in the wake of a tragic loss.

Explanation:

hope thsi helps if so please brainliest

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