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3 years ago

Which step of the scientific method involves identifying variables

Chemistry

2 answers:

Vlada [557]3 years ago

3 0

Testing a typothesiss

Marysya12 [62]3 years ago

3 0

The correct answer is:

Testing a hypothesis

Explanation:

Hypothesis testing is an action in statistics how an analyst tests a suspicion concerning a population parameter. Hypothesis testing is done to indicate the outcome of a hypothesis presented on individual data from a larger population. Hypothesis testing is an imperative idea in statistics. A hypothesis test estimates two together private statements about a population to settle which statement is best maintained by the sample data.

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A pea plant has the genotype Bb. What words describe this genotype?

blsea [12.9K]

The genetic combination of two alles

6 0

2 years ago

If an ultraviolet photon has a wavelength of 77.8 nm calculate the energy of one mole ultraviolet photon.

DerKrebs [107]

Answer:

Explanation:

E = (hc)/(λ)

E = (6.624x10^(-27))Js x ((3×10^8)ms^(-1)) /

(77.8x10^(-9)m)

E = 2.55 x 10^(-11) J

7 0

2 years ago

An inflatable toy starts with 1.05 moles of air and a volume of 5.17 liters. When fully inflated, the volume is 8.00 liters. If

padilas [110]

Answer:- 1.62 moles

Solution:- At constant temperature and pressure, volume is directly proportional to the moles of the gas.

$\frac{V_1}{V_2}=\frac{n_1}{n_2}$

from given data, $V_1$ = 5.17 L, $n_1$ = 1.05 moles

$V_2$ = 8.00 L, $n_2$ = ?

Let's plug in the values in the formula:

$\frac{5.17L}{8.00L}=\frac{1.05moles}{n_2}$

On cross multiply:

$n_2=\frac{8.00L(1.05moles)}{5.17L}$

$n_2$ = 1.62 moles

So, now the toy contains 1.62 moles of the air.

5 0

3 years ago

Ammonia is produced by the following reaction. 3H2(g) N2(g) Right arrow. 2NH3(g) When 7. 00 g of hydrogen react with 70. 0 g of

harkovskaia [24]

In the ammonia production process given by the reaction 3H₂(g) + N₂(g) → 2NH₃(g), when 7.00 g of hydrogen react with 70.0 g of nitrogen, hydrogen is considered the limiting reactant because 7.5 moles of hydrogen would be needed to consume the available nitrogen (option 1).

The reaction is the following:

3H₂(g) + N₂(g) → 2NH₃(g) (1)

To know why hydrogen is considered the limiting reactant, we need to calculate the number of moles of nitrogen and hydrogen with the following equation:

$n = \frac{m}{M}$

Where:

m: is the mass

M: is the molar mass

For hydrogen we have:

$n_{H_{2}} = \frac{m}{M} = \frac{7.00 g}{2.016 g/mol} = 3.47 \:moles$

And for nitrogen:

$n_{N_{2}} = \frac{m}{M} = \frac{70.0 g}{28.013 g/mol} = 2.50 \:moles$

We can see in reaction (1) that 3 moles of hydrogen react with 1 mol of nitrogen, so the number of hydrogen moles needed to react nitrogen is:

$n_{H_{2}} = \frac{3\:moles\:H_{2}}{1\:moles\:N_{2}}*n_{N_{2}} = \frac{3\:moles\:H_{2}}{1\:moles\:N_{2}}*2.50 \:moles = 7.50 \:moles$

Since we have 3.47 moles of hydrogen and we need 7.50 moles to react with all the mass of nitrogen, the limiting reactant is hydrogen.

We can find the number of ammonia moles produced with the limiting reactant (hydrogen) konwing that 3 moles of hydrogen produces 2 moles of ammonia, so:

$n_{NH_{3}} = \frac{2\:moles\:NH_{3}}{3\:moles\:H_{2}}*n_{H_{2}} = \frac{2\:moles\:NH_{3}}{3\:moles\:H_{2}}*3.47 \:moles = 2.31 \:moles$

Hence, hydrogen would produce 2.31 moles of ammonia.

Therefore, hydrogen is the limiting reactant because 7.5 moles of hydrogen would be needed to consume the available nitrogen (option 1).

Find more about limiting reactants here:

brainly.com/question/2948214?referrer=searchResults

I hope it helps you!

6 0

3 years ago

How might you explain the difference between the pH values of the 0.01 M HCl (pH = 1.1) and the 0.01 M HC2H3O2 (pH = 3.6)?

JulsSmile [24]

The difference is due to the degree of dissociation of the substances. HCl dissociates completely into ions when added to water, while this is not the case for HC₂H₃O₂; therefore, HCl has a lower pH.

7 0

3 years ago

Read 2 more answers