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3 years ago

In a controlled scientific experiment,a scientist

Chemistry

2 answers:

zmey [24]3 years ago

8 0

Answer: D

Explanation:

In a controlled scientific experiment, there should be an independent variable, a dependent variable, and a control. The independent variable is the factor in the experiment that is manipulated by the scientist. The dependent variable is the factor in the experiment that changes in response to the independent variable. Controls in an experiment are used as comparison factors, and they can help determine the magnitude of the experiment's results.

Scientists carefully control their variables so they can understand how the variables affect the system as a whole. This makes the data collected from an experiment meaningful.

s344n2d4d5 [400]3 years ago

5 0

The answer is D, alters the test variable, and observes the effects on other outcome variables.

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Which of the following does each different kind of atom represent?

3241004551 [841]

Answer:

Element

Explanation:

Each different kind of atom represents an atom. Elements like atoms are considered to be distinct substances that cannot be split into simpler substances. Such substances are known to be made up of just one kind of atom.

Like an atom, elements are made up of protons, neutrons and electrons. Both the protons and neutrons are found in the nucleus of the atom.

3 0

2 years ago

Show the calculation of the energy involved in condensation of 150 grams of steam at 100oC if the Heat of Vaporization for water

vaieri [72.5K]

Answer : The energy involved in condensation is, 339 kJ

Explanation :

Formula used :

$q=m\times L$

where,

q = heat required = ?

L = latent heat of vaporization of water = $2.26kJ/g$

m = mass of water = 150 g

Now put all the given values in the above formula, we get:

$q=(150g)\times (2.26kJ/g)$

$q=339kJ$

Therefore, the energy involved in condensation is, 339 kJ

4 0

3 years ago

If you start with 2 moles of Al and 2 moles of HCl, what will the limiting reactant be?

artcher [175]

Answer:

you have to give us the product in order for us to know the limiting reactant.

8 0

2 years ago

What is a substances heat capacity?

Phantasy [73]

Also called thermal capacity, is when the amount of heat required to raise the temp. of one mole or one gram of a substance by one degree Celsius without change of phase.

Hope this helps :)

6 0

3 years ago

What is the empirical formula of a compound with a percent composition of 22.5% Phosphorous and 77.5% Chlorine?

sashaice [31]

Answer:

$\boxed {\boxed {\sf PCl_3}}$

Explanation:

We are given the percent composition: 22.5% phosphorus and 77.5% chlorine.

We can assume there are 100 grams of this compound. We choose 100 because we can simply use the percentages as the masses.

22.5 g P
77.5 g Cl

Next, convert these masses to moles, using the molar masses found on the Periodic Table.

P: 30.974 g/mol
Cl: 35.45 g/mol

Use the molar masses as ratios and multiply by the number of grams. $22.5 \ g \ P * \frac {1 \ mol \ P }{30.974 \ g \ P}= \frac {22.5 \ mol \ P }{ 30.974} = 0.7264157035 \ mol \ P$

$77.5 \ g \ Cl * \frac {1 \ mol \ Cl }{35.45 \ g \ Cl}= \frac {77.5 \ mol \ Cl }{ 35.45} \ =2.186177715 \ mol \ Cl$

Divide both of the moles by the smallest number of moles to find the mole ratio.

$\frac {0.7264157035} {0.7264157035} = 1$

$\frac {2.186177715}{0.7264157035}=3.009540824 \approx 3$

The mole ratio is about 1 P: 3 Cl, so the empirical formula is written as:<u> PCl₃</u>

4 0

3 years ago