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
exis [7]
3 years ago
15

Describe the day of June 21 at the North Pole in terms of daylight and darkness ( science )

Chemistry
1 answer:
frosja888 [35]3 years ago
7 0
On June 21, as seen from the North pole ...

-- the sun has been up, and it's been light outside,
for the past three months ... ever since March 21 . 

-- The sun won't set, and it won't be dark outside,
for another three months ... until September 21.

-- Here at the North pole, it stays daylight for six months straight.
Today, on June 21, we're exactly halfway through the period of
continuous daylight.
You might be interested in
A sample of a pure compound that weighs 60.3 g contains 20.7 g Sb (antimony) and 39.6 g F (fluorine). What is the percent compos
Volgvan

Answer:

The percent composition of fluorine is 65.67%

Explanation:

Percent Composition is a measure of the amount of mass an element occupies in a compound. It is measured in percentage of mass.

That is, the percentage composition is the percentage by mass of each of the elements present in a compound.

The calculation of the percentage composition of an element is made by:

percent composition element A=\frac{total mass of element A}{mass of compound} *100

In this case, the percent composition of fluorine is:

percent composition of fluorine=\frac{39.6 g}{60.3 g} *100

percent composition of fluorine= 65.67%

<u><em>The percent composition of fluorine is 65.67%</em></u>

4 0
3 years ago
I NEED THESE ANSWERS ASAP
Snezhnost [94]
First one - Mg(OH)2+2HCl— MgCl2+ 2H2O
second one - CH4+2O2– 2H20
Third- is already balanced.
7 0
3 years ago
Oh hi thanks for checking in I’m still a piece of garbage ^_^^_^^_^^_^^_^^_^^_^^_^^_^^_^^_^^_^^_^^_^^ - ^
Ad libitum [116K]

Answer:

True

and same lol

7 0
2 years ago
Read 2 more answers
Which of the following buffers will be most effective at pH 9.25? Group of answer choices a mixture of 1.0 M HC2H3O2 and 1.0 M N
ludmilkaskok [199]

Answer:

The most effective buffer at pH 9.25 will be  a mixture of 1.0 M NH3 and 1.0 M NH4Cl

Explanation:

Step 1: Data given

pH of a buffer = pKa + log ([A-]/[Ha])

a mixture of 1.0 M HC2H3O2 and 1.0 M NaC2H3O2 (Ka for acetic acid = 1.8 x 10-5)

pH = -log( 1.8 * 10^-5) + log (1/1)

pH = -log( 1.8 * 10^-5)

pH = 4.74

a mixture of 1.0 M NaCN and 1.0 M KCN (Ka for HCN = 4.9 x 10-10)

pH = -log( 4.9 * 10^-10) + log (1/1)

pH = -log( 1.8 * 10^-5)

pH = 9.30

a mixture of 1.0 M HCl and 1.0 M NaCl

The solution made from NaCl and HCl will NOT act as a buffer.

HCl is a strong acid while NaCl is salt of strong acid and strong base which do not from buffer solutions hence due to HCl PH is less than 7.

a mixture of 1.0 M NH3 and 1.0 M NH4Cl (Kb for ammonia = 1.76 x 10^-5)

Ka * Kb = 1*10^-14

Ka = 10^-14 / 1.76*10^-5

Ka = 5.68*10^-10

pH = -log( 5.68*10^-10) + log (1/1)

pH = -log( 5.68*10^-10)

pH = 9.25

The most effective buffer at pH 9.25 will be  a mixture of 1.0 M NH3 and 1.0 M NH4Cl

8 0
2 years ago
When placed in a freezer , liquid water turns into ice . What best describes this change ?
GREYUIT [131]

Answer:

Freezing

Explanation:

liquid changing to a solid = Freezing

4 0
3 years ago
Read 2 more answers
Other questions:
  • Can someone help me with this???​
    9·1 answer
  • A solution is prepared by dissolving 91.7 g fructose in 545 g of water. Determine the mole fraction of fructose if the final vol
    12·1 answer
  • Which of the statements describes a chemical property?
    10·1 answer
  • 10 grams of sodium hydroxide, NaOH, is dissolved in 0.25 liters of solution. Determine the molarity (M).
    7·1 answer
  • 16. In which of these cases do we have enough information to say that the atom is electrically neutral? A. The atom has 15 neutr
    13·2 answers
  • Balance the following equation Sa+ F2---&gt; SF6
    14·1 answer
  • Vinegar, which contains acetic acid, is used in foods and has few safety concerns​. Hydrochloric acid is used in chemistry labs
    15·1 answer
  • What is the name of this compound?<br> N2O5
    12·2 answers
  • Chlorine has 7 valence electrons. Describe the type of bond that sodium would have
    15·1 answer
  • Are two atoms of the same element identical?
    7·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!