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Dimas [21]
3 years ago
8

Which scientist invented the first simple Microscope ?

Chemistry
1 answer:
Vinvika [58]3 years ago
6 0

Answer:

D.  Leeuwenhoek

Explanation:

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What occurs during a slump?
abruzzese [7]

Answer:

A slump is a form of mass wasting that occurs when a coherent mass of loosely consolidated materials or a rock layer moves a short distance down a slope.[1] Movement is characterized by sliding along a concave-upward or planar surface. Causes of slumping include earthquake shocks, thorough wetting, freezing and thawing, undercutting, and loading of a slope.

3 0
2 years ago
How many valence electrons does chlorine have?
Advocard [28]
Valence Electrons has \boxed{7} chlorine
3 0
3 years ago
Read 2 more answers
What is the nuclear binding energy for thorium-234? 2.78 × 10-10 J 3.36 × 10-14 J 1.67 × 1017 J 5.35 x 10-23 J
grin007 [14]
The correct option is A.
To calculate the binding energy, you have to find the mass defect first.
Mass defect = [mass of proton and neutron] - Mass of the nucleus
The molar mass of thorium that we are given in the question is 234, the atomic number of thorium is 90, that means the number of neutrons in thorium is 
234 - 90 = 144.
The of proton in thourium is 90, same as the atomic number.
Mass defect = {[90 * 1.00728] +[144* 1.00867]} - 234
Note that each proton has a mass of 1.00728 amu and each neutron has the mass of 1.00867 amu.
Mass defect = [90.6552 + 145.24848] - 234 = 1.90368 amu.
Note that the unit of the mass is in amu, it has to be converted to kg
To calculate the mass in kg
Mass [kg] = 1.90368 * [1kg/6.02214 * 10^-26 = 3.161135 * 10^-27
To calculate the binding energy
E = MC^2
C = Speed of light constant = 2.9979245 *10^8 m/s2
E = [3.161135 * 10^-27] * [2.9979245 *10^8]^2
E = 2.84108682069 * 10^-10.
Note that we arrive at this answer because of the number of significant figures that we used.
So, from the option given, Option A is the nearest to the calculated value and is our answer for this problem.

8 0
3 years ago
Read 2 more answers
Determine the number of moles in 4.21 x 10^23 molecules of CaCI2?????
Alla [95]

Explanation:

Given parameters:

Number of molecules = 4.21 x 10²³ molecules

Unknown parameters:

Number of moles

Solution:

A mole can be defined as the amount of a substance that contains the avogadro's number of particles i.e 6.02 x 10²³

  To find the number of moles:

          Number of moles = \frac{number of molecules }{[tex]6.02 x 10^{23}}[/tex]

  Number of moles =  \frac{4.21 x 10[tex]^{23} }{6.02 x 10^{23}}[/tex]

Number of moles of CaCl₂ = 0.699moles

Learn more;

mole calculation brainly.com/question/13064292

#learnwithBrainly

8 0
3 years ago
If it is 9 am in San Francisco, is it also 9 am in New York? Why or why not?
lys-0071 [83]

Answer:

san franciso is 3 hours beind and with NewYork

Explanation:

5 0
2 years ago
Read 2 more answers
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