1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
ivanzaharov [21]
3 years ago
13

What affect does attendance have on students' grades in science class? Write the independent variable, the dependent variable, a

nd the hypothesis.
Chemistry
1 answer:
alexira [117]3 years ago
6 0
Independent variable: the student chooses to miss class.
dependent variable: in result of the student missing class his grade goes down.
hyposthesis: if the student misses class multiple times, then his grades will go down.
You might be interested in
What kind of reaction is represented by the dancing figures?
Darina [25.2K]
C - single replacement reaction
6 0
3 years ago
The sun emits electromagnetic waves at many frequencies, but mostly in the infrared, visible, and ultraviolet
meriva
The correct answer is radiant, radiant that get transferred into chemical energy
3 0
4 years ago
Read 2 more answers
The chemical standard for the quantity of a mole is based on which substance?
alexandr402 [8]
A mole is mean the atomic number of 12 grams of carbon 12.
3 0
4 years ago
Green light has a wavelength of 550nm. What is the frequency of a photon of green light?
Vikki [24]

Answer:- Frequency is 5.4*10^1^4Hz .

Solution:- frequency and wavelength are inversely proportional to each other and the equation used is:

\nu =\frac{c}{\lambda }

where, \nu is frequency, c is speed of light and \lambda is the wavelength.

Speed of light is 3.0*10^8m/s .

We need to convert the wavelength from nm to m.

( 1nm=10^-^9m )

550nm(\frac{10^-^9m}{1nm})

= 5.5*10^-^7m

Now, let's plug in the values in the equation to calculate the frequency:

\nu =\frac{3.0*10^8m.s^-^1}{5.5*10^-^7m}

= 5.4*10^1^4s^-^1 or 5.4*10^1^4Hz

since, 1s^-^1=1Hz

So, the frequency of the green light photon is 5.4*10^1^4Hz .

4 0
3 years ago
Using the following reaction (depicted using molecular models), large quantities of ammonia are burned in the presence of a plat
Mila [183]

Answer:

17.65 grams of O2 are needed for a complete reaction.

Explanation:

You know the reaction:

4 NH₃ + 5 O₂ --------> 4 NO + 6 H₂O

First you must know the mass that reacts by stoichiometry of the reaction (that is, the relationship between the amount of reagents and products in a chemical reaction). For that you must first know the reacting mass of each compound. You know the values ​​of the atomic mass of each element that form the compounds:

  • N: 14 g/mol
  • H: 1 g/mol
  • O: 16 g/mol

So, the molar mass of the compounds in the reaction is:

  • NH₃: 14 g/mol + 3*1 g/mol= 17 g/mol
  • O₂: 2*16 g/mol= 32 g/mol
  • NO: 14 g/mol + 16 g/mol= 30 g/mol
  • H₂O: 2*1 g/mol + 16 g/mol= 18 g/mol

By stoichiometry, they react and occur in moles:

  • NH₃: 4 moles
  • O₂: 5 moles
  • NO: 4 moles
  • H₂O: 6 moles

Then in mass, by stoichiomatry they react and occur:

  • NH₃: 4 moles*17 g/mol= 68 g
  • O₂: 5 moles*32 g/mol= 160 g
  • NO: 4 moles*30 g/mol= 120 g
  • H₂O: 6 moles*18 g/mol= 108 g

Now to calculate the necessary mass of O₂ for a complete reaction, the rule of three is applied as follows: if by stoichiometry 68 g of NH₃ react with 160 g of O₂, 7.5 g of NH₃ with how many grams of O₂ will it react?

mass of O_{2} =\frac{7.5 g of NH_{3} * 160 g of O_{2} }{68 g of NH_{3} }

mass of O₂≅17.65 g

<u><em>17.65 grams of O2 are needed for a complete reaction.</em></u>

3 0
3 years ago
Other questions:
  • What symbol is that plz tell
    15·1 answer
  • So like i honestly forgot abt this so if you could explain.. :)
    12·2 answers
  • Express in scientific notation. Make sure your answer has the same number of significant figures as the starting value.
    12·1 answer
  • Elements are arranged in groups by similar atomic structure on the periodic table. This allows for an element’s properties to be
    10·2 answers
  • Onsider this representation of an original DNA sequence: THE TALL MAN WAS SAD.
    7·2 answers
  • Convection is the transfer of heat through the rising and sinking of a fluid. A student is constructing an explanation for how c
    8·2 answers
  • Please and thank you
    12·2 answers
  • The step by step direction of a experiment are found in...
    11·1 answer
  • What type of bond involves the unequal sharing of electrons.
    7·1 answer
  • A small region of a cancer patient’s brain is exposed for 24.0 min to 475 Bq of radioactivity from⁶⁰Co for treatment of a tumor.
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!