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
GrogVix [38]
3 years ago
13

Why is Darwins theory of evolution by natural selection not just a theory

Chemistry
1 answer:
Mamont248 [21]3 years ago
4 0

Answer:

it talks about reality ..how animals and human came to existence and how they disappear ..this is evolution

the environment chooses those who best fit in it and others are selected ..as in die ..this is referred to as natural selection

and further in this theory .animals produce off springs who survive in the environment

You might be interested in
Identify the major attractive force in HF molecules.A) London Dispersion Forces (LDFs)
Llana [10]

Answer:

C) hydrogen bonding

Explanation:

All atoms and molecules have London Dispersion Forces between them, but they are usually overshadowed but the much stronger forces. In this scenario the major attractive force in HF molecules are hydrogen bonds. Hydrogen bonds are electrostatic forces of attraction found when Hydrogen is bonded to a more electronegative atom such as Oxygen, Chlorine and Fluorine.

6 0
3 years ago
What units are used to measure energy? A) volts B) angstroms C) centimeters D) joules
Usimov [2.4K]

Answer:

joules

Explanation:

it is the measurement of energy

7 0
3 years ago
During the chemical reaction given below 21.71 grams of each reagent were allowed to react. Determine how many grams of the exce
swat32

Answer: 16.32 g of O_2 as excess reagent are left.

Explanation:

To calculate the moles :

\text{Moles of solute}=\frac{\text{given mass}}{\text{Molar Mass}}    

\text{Moles of} SO_2=\frac{21.71g}{64g/mol}=0.34mol

\text{Moles of} O_2=\frac{21.71g}{32g/mol}=0.68mol

2SO_2(g)+O_2(g)\rightarrow 2SO_3(g)  

According to stoichiometry :

2 moles of SO_2 require = 1 mole of O_2

Thus 0.34 moles of SO_2 will require=\frac{1}{2}\times 0.34=0.17moles  of O_2

Thus SO_2 is the limiting reagent as it limits the formation of product and O_2 is the excess reagent.

Moles of O_2 left = (0.68-0.17) mol = 0.51 mol

Mass of O_2=moles\times {\text {Molar mass}}=0.51moles\times 32g/mol=16.32g

Thus 16.32 g of O_2 as excess reagent are left.

3 0
2 years ago
How has СOVID-19 demonstrated<br> the process of the scientific<br> method for the public?
Vesnalui [34]

Answer:

none

Explanation:

none

7 0
3 years ago
A chemist measures the enthalpy change ?H during the following reaction: Fe (s) + 2HCl (g) ? FeCl2 (s) + H2 (g) =?H?157.kJ Use t
erik [133]

Correct Question:

A chemist measures the enthalpy change ΔH during the following reaction: Fe(s) + 2HCl(g)-->FeCl2(s) + H2 ΔH=-157.0 kJ. Use this information to complete the table below. Round each of your answers to the nearest kJ/mol

Answer:

-314 kJ

+628 kJ

+157 kJ

Explanation:

The enthalpy change of a reaction measures the amount of heat that is lost or gained by it. If ΔH >0 the heat is gained, and the reaction is called endothermic, if ΔH<0, the heat is lost, and the reaction is called exothermic.

If the reaction is inverted, the value of ΔH is inverted too (the opposite endothermic reaction is exothermic), and if the reaction is multiplied by a constant, ΔH will be multiplied by it too.

1) 2Fe(s) + 4HCl --> 2FeCl2(s) + 2H2(g)

This reaction is the product of the given reaction by 2, so

ΔH = 2*(-157) = -314 kJ

2) 4FeCl2(s) + 4H2(g) --> 4Fe(s) + 8HCl(g)

This reaction is the inverted reaction given multiplied by 4, so

ΔH = 4*(157) = +628 kJ

3) FeCl2(s) + H2(g) --> Fe(s) + 2HCl

This reaction is the inverted reaction given, so

ΔH = +157 kJ

4 0
3 years ago
Other questions:
  • The reaction between aluminium powder and iron(III) oxide is used in the rail industry. a. i) write a word equation and a balanc
    11·1 answer
  • Calculate Ecell at 80 ºC for a voltaic cell based on the following redox reaction: H2(g, 1.25 atm) + 2AgCl(s) → 2Ag(s) + 2H+(aq,
    13·1 answer
  • What do repeated trials in an experiment allow a scientist to do?
    11·1 answer
  • Is the movement of plates to form land masses is called plate tectonics
    10·1 answer
  • *WILL GIVE BRAINLIEST IF SOMEONE ANSWERS THIS CORRECTLY ASAP!!!!*
    5·2 answers
  • How many atoms are in 2 miles of h2o
    8·1 answer
  • You have made use of the Le Chatelier principle in this lab. Explain how the Le Chatelierprinciple is used to help formation of
    9·1 answer
  • The concentration of copper(II) sulfate in one brand of soluble plant fertilizer is 0.070% by weight. If a 21.5 g sample of this
    13·1 answer
  • A substance has a molecular formula of C8H10N4O2
    10·1 answer
  • Which process does NOT lead to a decrease in the salinity of water?
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!