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
PolarNik [594]
3 years ago
13

This infectious disease requires a special mask for protection

Chemistry
2 answers:
11111nata11111 [884]3 years ago
6 0

Answer:

the black plague

Explanation:

Yuliya22 [10]3 years ago
6 0

Answer:

no

Explanation:

becuase the only way you need to have a special mask is if it was constantly changing

You might be interested in
What are two things with the same volume but different masses?
Sati [7]

Answer:

an ice cube and paper cube with the same dimensions

Explanation:

an example is an ice cube and a cube with the same dimensions made of paper. these have the same volume, but different masses because the particles are packed differently and in different amounts.

7 0
2 years ago
21. _____ Which of the following entities has the greatest mass?
IrinaK [193]
I believe it’s D because phosphorus has the mass of 30.9.
8 0
2 years ago
State the oxidation number assigned to each bold element in the formula: NH4+1 a 3 b -3 c -1 d 6
Leya [2.2K]
The fomula is NH4 (1+)


There are only two elements N and H.


As per oxidation state rules, the most electronegative element will have a negative oxidation state and the other element will have a positive oxidation state.


N is more electronative than H, so H will have a positive oxidation state and nitrogen will have a negative oxidation state.


You can also use the rule that states the hydrogen mostly has 1+ oxidation state,except when it is bonded to metals.


In conclusion the oxidation state of H in NH4 (1+) is 1+.


Now you must know that the sum of the oxidations states equals the charge of the ion, which in this case is 1+.


That implies that 4* (1+)  + x =   1+


=> x = (1+) - 4(+) = 3-


Answer:  the oxidation state of N is 3-, that is the option b.
8 0
3 years ago
Could somebody please give me an example of some physical properties for any substance?
KIM [24]

Answer:

A physical property is a characteristic of matter that is not associated with a change in its chemical composition. Familiar examples of physical properties include density, color, hardness, melting and boiling points, and electrical conductivity.

Explanation:

6 0
2 years ago
URGENT PLEASE HELP!! Earth science!!
aev [14]

Answer:

URGENT PLEASE HELP!! Earth science!!

What stages of development are represented by the Group 2 and Group 3 stars? Describe these

groups in terms of their relative age, size, brightness, and temperature.

3 0
2 years ago
Other questions:
  • Your friend makes the statement that, “Water boils at a higher temperature than ethanol.” To which step of the scientific method
    9·1 answer
  • How many moles are in 2.0 grams of FeO
    14·2 answers
  • How many colors would you see if you were analyzing a pure substance through chromatography?
    12·2 answers
  • What word describes the splitting of a larger atom into smaller ones?
    11·2 answers
  • 14. What steps should you take to keep parents and the public from viewing your personal
    5·1 answer
  • Phosphoric acid is a triprotic acid with the following pKa values:pKa1=2.148, pKa2=7.198, pKa3=12.375You wish to prepare 1.000 L
    12·1 answer
  • The best thermometer to use where temperatures drop below -39°C (-38.2°F) is:_______.
    8·1 answer
  • What does the "R-" represent?
    9·2 answers
  • Which of the following is NOT a "big idea" in chemistry?
    10·1 answer
  • What is the temperature of 0. 750 mol of a gas stored in a 6,850 ml cylinder at 2. 21 atm?.
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!