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3 years ago

5

Suppose you have a scientific question you are interested in answering. What would you normally do before you make your hypothes

is? A. Do some background research. B. Conduct a scientific experiment. C. Make predictions about your question. D. Design a procedure for your experiment.

2 answers:

hoa [83]3 years ago

7 0

Answer:

aaaaaaaaaa

Explanation:

STatiana [176]3 years ago

6 0

Answer:

A. Do some background research

There are 5 steps for the scientific method while doing an experiment

Step 1: make a question

Step 2: research that question

Step 3: Hypothesis

Step 4: Test and collect data

Step 5: Conclusion

You might be interested in

The reaction of NO2 with ozone produces NO3 in a second-order reaction overall.

Brilliant_brown [7]

Answer : The rate of reaction is,

$Rate=4.77\times 10^{-19}M/s$

The appearance of $NO_3$ is, $4.77\times 10^{-19}M/s$

Explanation :

The general rate of reaction is,

$aA+bB\rightarrow cC+dD$

Rate of reaction : It is defined as the change in the concentration of any one of the reactants or products per unit time.

The expression for rate of reaction will be :

$\text{Rate of disappearance of A}=-\frac{1}{a}\frac{d[A]}{dt}$

$\text{Rate of disappearance of B}=-\frac{1}{b}\frac{d[B]}{dt}$

$\text{Rate of formation of C}=+\frac{1}{c}\frac{d[C]}{dt}$

$\text{Rate of formation of D}=+\frac{1}{d}\frac{d[D]}{dt}$

$Rate=-\frac{1}{a}\frac{d[A]}{dt}=-\frac{1}{b}\frac{d[B]}{dt}=+\frac{1}{c}\frac{d[C]}{dt}=+\frac{1}{d}\frac{d[D]}{dt}$

From this we conclude that,

In the rate of reaction, A and B are the reactants and C and D are the products.

a, b, c and d are the stoichiometric coefficient of A, B, C and D respectively.

The negative sign along with the reactant terms is used simply to show that the concentration of the reactant is decreasing and positive sign along with the product terms is used simply to show that the concentration of the product is increasing.

The given rate of reaction is,

$NO_2(g)+O_3(g)\rightarrow NO_3(g)+O_2(g)$

The rate law expression will be:

$Rate=k[NO_2][O_3]$

Given:

Rate constant = $k=1.69\times 10^{-4}M^{-1}s^{-1}$

$[NO_2]$ = $1.77\times 10^{-8}M$

$[O_3]$ = $1.59\times 10^{-7}M$

$Rate=k[NO_2][O_3]$

$Rate=(1.69\times 10^{-4})\times (1.77\times 10^{-8})\times (1.59\times 10^{-7})$

$Rate=4.77\times 10^{-19}M/s$

The expression for rate of appearance of $NO_3$ :

$\text{Rate of reaction}=\text{Rate of appearance of }NO_3=+\frac{d[NO_3]}{dt}$

As, $\text{Rate of reaction}=4.77\times 10^{-19}M/s$

So, $\text{Rate of appearance of }NO_3=+\frac{d[NO_3]}{dt}=4.77\times 10^{-19}M/s$

Thus, the appearance of $NO_3$ is, $4.77\times 10^{-19}M/s$

7 0

3 years ago

What is the total mass of 25.04 gram

GarryVolchara [31]

Answer:

What is the absolute temperature of this gas sample when the pressure is ... The total mass of the water vapor is 0.252 g ... A silver spoon with a mass of 25.04 g at a temperature of 100.00 ... A 0.821 gram sample of pure NH F was treated with 25.0 mL of 1.00 M NaOH and heated to drive off the NH, a.

Explanation:

4 0

3 years ago

Find the concentration of H+ ions at a pH = 11 and

Black_prince [1.1K]

Explanation:

the pH of the solution defined as negatuve logarithm of $H^+$ ion concentration.

$pH=-\log[H^+]$

1. Hydrogen ion concentration when pH of the solution is 11.

$11=-\log[H^+]$

$[H^+]=1\times 10^{-11} mol/L$ ..(1)

At pH = 11, the concentration of $H^+$ ions is $1\times 10^{-11} mol/L$ .

2. Hydrogen ion concentration when the pH of the solution is 6.

$6=-\log[H^+]'$

$[H^+]'=1\times 10^{-6} mol/L$ ..(2)

At pH = 6, the concentration of $H^+$ ions is $1\times 10^{-6} mol/L$ .

3. On dividing (1) by (2).

$\frac{[H^+]}{[H^+]'}=\frac{1\times 10^{-11} mol/L}{1\times 10^{-6} mol/L}=1\times 10^{-5}$

The ratio of hydrogen ions in solution of pH equal to 11 to the solution of pH equal to 6 is $1\times 10^{-5}$ .

4. Difference between the $H^+$ ions at both pH:

$1\times 10^{-6} mol/L-1\times 10^{-11} mol/L=9.99\time 10^{-7} mol/L$

This means that Hydrogen ions in a solution at pH = 7 has $9.99\time 10^{-7} mol/L$ ions fewer than in a solution at a pH = 6

6 0

3 years ago

Read 2 more answers

Jack lives in a small city in the Pacific Northwest, where the temperatures are cool all year and the sky is frequently cloudy a

kirill [66]

Answer:

Preocouparcor ,imsm oilp

Explanation:

3 0

3 years ago

An acid sample of an unknown concentration is contained in a erlenmeyer flask. Which technique below would be best suited to ana

Ivenika [448]

Answer:

Titration

Explanation:

The best technique which can be used to determine the number of moles of the HCl in the sample is titration.

The given amount of HCl solution must be titrated with known concentration of the base like NaOH.

The volume of NaOH required must be noted also.

According to the reaction,

$NaOH+HCl\rightarrow NaCl+H_2O$

At equivalence point

Moles of $HCl$ = Moles of $NaOH$

Considering:-

Moles of $HCl=Molarity_{NaOH}\times Volume_{NaOH}$

Thus, in this way, moles of HCl can be determined.

4 0

3 years ago