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
zhuklara [117]
2 years ago
11

How many significant figures are in the measurement 40, 500 mg? a) two b) three c) four d) five

Chemistry
1 answer:
emmainna [20.7K]2 years ago
8 0
I believe there are 3 significant figures B.
You might be interested in
PLEASE HELP ME I HAVE NO IDEA “Heat (thermal) energy is being applied to the substance whenever the Bunsen Burner is on. Before
svetlana [45]

TLDR: The energy was being used simply to heat the substance up.

Whenever something melts, it performs what is called a "phase transition", where the state of matter moves from one thing to something else. You can see this in your iced drink at lunch; as the ice in the cup of liquid heats up, it reaches a point where it will eventually "change phase", or melt. The same can be achieved if you heat up that water enough, like if you're cooking; when you boil eggs, the water has so much thermal energy it can "change phase" and become a gas!

However, water doesn't randomly become a boiling gas, it has to heat up for a while before it reaches that temperature. For a real-life example, the next time you cook something, hold you hand above the water before it starts boiling. You'll see that that water has quite a high temperature despite not boiling.

There's a lot of more complex chemistry to describe this phenomena, such as the relationship between the temperature, pressure, and what is called the "vapor pressure" of a liquid when describing phase changes, but for now just focus on the heating effect. When ice melts, it doesn't seem like its heating up, but it is. The ice absorbs energy from its surroundings (the warmer water), thus heating up the ice and cooling down the water. Similarly, the bunsen burner serves to heat up things in the lab, so before the solid melts in this case it was simply heating up the solid to the point that it <u>could</u> melt.

Hope this helps!

5 0
3 years ago
What type of particles move to create electicity?<br> electrons<br> protons<br> neutrons
sladkih [1.3K]

the answer is electrons.....

5 0
3 years ago
A lime has a [H+] concentration of 0.0120 M.<br><br> What is the pH of the lime? 3 sig figs
Novosadov [1.4K]

Answer: pH= 1.92

Explanation:

pH= -log[H+]

pH= -log[0.012]

= 1.92

4 0
3 years ago
When 2.50 g of an unknown weak acid (ha) with a molar mass of 85.0 g/mol is dissolved in 250.0 g of water, the freezing point of
baherus [9]
When dT = Kf * molality * i
                = Kf*m*i
and when molality = (no of moles of solute) / Kg of solvent
                               = 2.5g /250g x 1 mol /85 g x1000g/kg
                               =0.1176 molal
and Kf for water = - 1.86 and dT = -0.255
by substitution 
0.255 = 1.86* 0.1176 * i
∴ i = 1.166
when the degree of dissociation formula is: when n=2 and  i = 1.166
a= i-1/n-1 = (1.166-1)/(2-1) = 0.359 by substitution by a and c(molality) in K formula
∴K = Ca^2/(1-a)
     = (0.1176 * 0.359)^2 / (1-0.359)
     = 2.8x10^-3



5 0
2 years ago
Determine the volume of occupied by 4 moles of carbon dioxide gas at
valentina_108 [34]

Answer:

Vol of 4 moles CO₂(g) at STP = 89.6 Liters

Explanation:

STP

P = 1 Atm

V =

T = 0°C = 273 K

n = 4 moles

R = 0.08206 L·Atm/mol·K

Using Ideal Gas Law PV = nRT => V = nRT/P

V = (4 moles)(0.08206 L·Atm/mol·K)(273 K)/(1 Atm) = 89.6 Liters

5 0
3 years ago
Other questions:
  • About half of the electricity in the United States is generated using _____. natural gas biomass coal hydropower
    9·2 answers
  • The water at the top of a waterfall has _____ energy.
    15·2 answers
  • Based on the number of valence electrons indicated by its location in the periodic table, which element's behavior would you pre
    11·1 answer
  • One molecule of the oxide of element Z reacts with six molecules of water to
    8·1 answer
  • A houseplant is placed on a window sill that gets direct, bright sunlight
    15·1 answer
  • How many grams are in 3.93 x 10^24 molecules of CCl4?
    9·1 answer
  • The following chemical equations are organized by reaction type. You must balance each reaction, and show your work
    5·1 answer
  • 1. How many atoms of chlorine are present in 1.70x1023 molecules Cl2?​
    11·1 answer
  • What do the digestive system and skeletal system have in common?
    6·1 answer
  • In one to two sentences, identify and describe the processes that must happen for sand to eventually become metamorphic rock.
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!