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
Sophie [7]
4 years ago
8

Which are compounds, which are elements and which are mixtures?

Chemistry
1 answer:
Kamila [148]4 years ago
5 0

Answer:

first first row: element

second first row :compound

You might be interested in
A certain drug has a half-life in the body of 3.5h. Suppose a patient takes one 200.Mg pill at :500PM and another identical pill
tekilochka [14]

Answer:

The amount of drug left in his body at 7:00 pm is 315.7 mg.

Explanation:

First, we need to find the amount of drug in the body at 90 min by using the exponential decay equation:

N_{t} = N_{0}e^{-\lambda t}

Where:

λ: is the decay constant = ln(2)/t_{1/2}

t_{1/2}: is the half-life of the drug = 3.5 h

N(t): is the quantity of the drug at time t

N₀: is the initial quantity

After 90 min and before he takes the other 200 mg pill, we have:

N_{t} = 200e^{-\frac{ln(2)}{3.5 h}*90 min*\frac{1 h}{60 min}} = 148.6 mg

Now, at 7:00 pm we have:

t = 7:00 pm - (5:00 pm + 90 min) = 30 min

N_{t} = (200 + 148.6)e^{-\frac{ln(2)}{3.5 h}*30 min*\frac{1 h}{60 min}} = 315.7 mg    

Therefore, the amount of drug left in his body at 7:00 pm is 315.7 mg (from an initial amount of 400 mg).

I hope it helps you!

3 0
3 years ago
Wat is significant figures
Sav [38]

<em>Answer:</em>

  •                   0.052301 km have 5 significant figure
  •                   400 cm have 1 significant figure
  •                   50.0 m  have 3 significant figure
  •                  4500.01 ml have 6 significant figure

<em>Explanation:</em>

According to rules of significant figure

0.052301 km have 5 significant figure:

  • Zero to the left of the first non zero digit not significant.
  • Zero between the non zero digits are significant.

<em>400 cm have 1 significant figure:</em>

  • Trailing zeros are not significant in numbers without decimal points.

<em>50.0 m  have 3 significant figure:</em>

  • Trailing zeros are significant in numbers when there is decimal points.

<em>4500.01 ml have 6 significant figure:</em>

  • Zero between the non zero digits are significant.
4 0
4 years ago
b) If 1.5 mole of oxygen reacted, how many mole of iron (III) oxide would be formed from the reaction?
lyudmila [28]

Answer:

If there reacted 1.5 moles of O2, there will be produced 1.0 mol of Fe2O3

Explanation:

Step 1: Data given

Number of moles oxygen reacted = 1.5 moles

Step 2: The balanced equation

4Fe + 3O2 → 2Fe2O3

Step 3: Calculate moles of Fe2O3

For 4 moles Fe consumed, we need 3 moles of O2 to produce 2 moles of Fe2O3

For 1.5 moles O2 consumed, we'll have 2/3 * 1.5 = 1.0 mol of Fe2O3

If there reacted 1.5 moles of O2, there will be produced 1.0 mol of Fe2O3

7 0
3 years ago
Convert 25 gigaseconds into centiseconds​
dangina [55]

25 gigaseconds is equal to 2,500,000,000,000 centiseconds

6 0
3 years ago
Write the molecular formula in the of the following compounds.
tensa zangetsu [6.8K]
Calcium bicarbonate - Ca(HCO3)2
sodium peroxide - Na202
water - H20
silver nitrate - AgN03
potassium carbonate - K2CO3
sodium carbonate - Na2CO3
zinc chloride - ZnC12
calcium hydroxide - Ca(OH)2
magnesium chloride - MgC12
4 0
3 years ago
Other questions:
  • At a certain temperature this reaction follows second-order kinetics with a rate constant of 0.118 M^-1* s^-1:
    13·1 answer
  • 1) You are asked to make 10 miles of iron (Fe) from iron oxide (Fe2O3) and excess carbon monoxide (CO). Fe2O3(s) + 3CO(g)—&gt; 2
    10·1 answer
  • The atomic number of nitrogen is 7. The number of electrons a neutral nitrogen atom has is _______ , and its atomic mass is appr
    12·2 answers
  • how will the following systems react when an increase in pressure occurs? note all species are gases N2O4&lt;--&gt;2NO2
    15·1 answer
  • Sulfur reacts with oxygen to produce sulfur trioxide gas. Balance the equation. __S+__(sub2) -----&gt; __SO(sub3)
    7·1 answer
  • Give the major organic products from the oxidation with KMnO4 for the following compounds. Assume an excess of KMnO4.
    8·1 answer
  • Which choice contains a FALSE statment? A. For the vaporization of liquid benzene ΔH is positive. B. For the formation of 1 mol
    8·1 answer
  • Joanne has to undergo a________ in order to repair her breasts.
    8·1 answer
  • Write the separation scheme for the isolation of triphenylmethanol from the reaction mixture once the reaction is complete. The
    12·1 answer
  • 00000044m<br> 300000km/s <br> Both in scientific notation
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!