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2 years ago

15

Your bus is traveling 80 km/hr on a class trip to a museum that is 240 kilometers from your school. How long will it take to get

there?

1 answer:

DochEvi [55]2 years ago

7 0

I believe it’s 3 hours since every hour it’s 80km so 3x80 is 240 so it would be 3 hours.

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What does it mean to be "moderated by water"?

scZoUnD [109]

water is watching over you

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4 years ago

Read 2 more answers

A) 2Fe(s) + O2(g) =>

TiliK225 [7]

Answer: -22.2 kJ

Explanation:

According to Hess’s law of constant heat summation, the heat absorbed or evolved in a given chemical equation is the same whether the process occurs in one step or several steps. SGDSDGSDGSDGgsg

According to Hess’s law, the chemical equation can be treated as algebraic expressions and can be added or subtracted to yield the required equation. That means the enthalpy change of the overall reaction is the sum of the enthalpy changes of the intermediate reactions.

(1) $2Fe(s)+O_2(g)\rightarrow 2FeO(s)$ $\Delta H_1=-544.0kJ$

(2) $4Fe(s)+O_2(g)\rightarrow 2Fe_2O_3(s)$ $\Delta H_2=-1648.4kJ$

(3) $Fe_3O_4(s)\rightarrow 3Fe(s)+2O_2(g)$ $\Delta H=+1118.4kJ$

Reversing 1 ,2 and 3 and halving 1 and 2 and then adding we get net equation:

(4) $Fe_2O_3(s)+FeO(s)\rightarrow Fe_3O_4(s)$ $\Delta H_4=?$

$\Delta H_4=\frac{-\Delta H_1}{2}+\frac{-\Delta H_2}{2}+(-\Delta H_3)=\frac{544.0}{2}+\frac{1648.4}{2}+(-1118.4)=-22.2kJ$

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3 years ago

1. Choose the alkyl halide(s) from the following list of C6H13Br isomers that meet each criterion below. 1) 1-bromohexane 2) 3-b

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Answer:

See explanation

Explanation:

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3-bromo-3-methylpentane

the compound(s) that can exist as diastereomers - 3-bromo-3-methylpentane

the compound(s) that can exist as enantiomers- 3-bromo-2-methylpentane

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3 years ago

A sample of rainwater is tested with the indicator bromothymol blue and it turns yellow. What is most likely PH of rainwater? 4,

kirill [66]

Answer:

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4 years ago

A second-order reaction has a rate constant of 1.25 M-1 s-1. If the initial reactant concentration is 1.0 M (a) determine the ha

Ne4ueva [31]

Answer:

(a) 0.8 s

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Explanation:

(a) Half life expression for second order kinetic is:

$t_{1/2}=\frac{1}{k[A_o]}$

Where,

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So,

$t_{1/2}=\frac{1}{1.25\times 1.0}$

Half life = 0.8 s

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$\frac{1}{[A_t]} = \frac{1}{[A]_0}+kt$

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$\frac{1}{0.1} = \frac{1}{1.0}+1.25t$

t = 7.2 s

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3 years ago