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2 years ago

What evidence did Wegener use to support his continental drift hypothesis?

Chemistry

1 answer:

Mrac [35]2 years ago

6 0

Answer: Coastlines.

Explanation: South America's and Africa's shoreline interlocks perfectly. Which implies they must have been joined together in history.

You might be interested in

Which of the following has the most energy?

iren2701 [21]

Ultraviolet rays has the most energy

8 0

2 years ago

Ions of an element (elements with different charges) contain different numbers of what

Vadim26 [7]

Answer:

an ion is an element that has different numbers of protons and electrons

Explanation:

An ion is positive when it has more protons than electrons and negative when it has more electrons than ions.

(Hope this was helpful!) :)

7 0

2 years ago

Which aqueous solution has the lowest freezing point c6h12o6, c2h5oh, ch3cooh, or nacl?

Eddi Din [679]

Depression of a freezing point of the solutions depends on the number of particles of the solute in the solution.
1 mol of C6H12O6 after dissolving in water still be 1 mol, because C6H12O6 does no dissociate in water.
1 mol of C2H5OH after dissolving in water still be 1 mol, because C2H5OH does no dissociate in water.
1 mol of NaCl after dissolving in water gives 2 mol of particles (ions), because NaCl is a strong electrolyte(as salt) and completely dissociates in water.
NaCl ----->Na⁺ + Cl⁻
1 mol of CH3COOH after dissolving in water gives more than 1 mol but less than 2 moles, because CH3COOH is a weak electrolyte (weak acid) and dissociates only partially.

So, most particles of the solute is going to be in the solution of NaCl,
so<span> the lowest freezing point has the aqueous solution of NaCl.</span>

3 0

2 years ago

Radioactive decay can be described by the following equation where is the original amount of the substance, is the amount of the

soldi70 [24.7K]

Answer:

Iron remains = 17.49 mg

Explanation:

Half life of iron -55 = 2.737 years (Source)

$t_{1/2}=\frac {ln\ 2}{k}$

Where, k is rate constant

So,

$k=\frac {ln\ 2}{t_{1/2}}$

$k=\frac {ln\ 2}{2.737}\ year^{-1}$

The rate constant, k = 0.2533 year⁻¹

Time = 2.41 years

$[A_0]$ = 32.2 mg

Using integrated rate law for first order kinetics as:

$[A_t]=[A_0]e^{-kt}$

Where,

$[A_t]$ is the concentration at time t

$[A_0]$ is the initial concentration

So,

$[A_t]=32.2\times e^{-0.2533\times 2.41}\ mg$

$[A_t]=32.2\times e^{-0.610453}\ mg$

$[A_t]=17.49\ mg$

<u>Iron remains = 17.49 mg</u>

8 0

2 years ago

• Draw lewis dot structures for an atom of each of following elements:

marin [14]

Answer:

Explanation:

Lewis dot structures represent the symbol of an atom we're looking at and the number of valence electrons it has. This number is represented by the sum of dots around the symbol.

Potassium is in group 1A, this means it only has one valence electron, so we draw K with one dot in its Lewis diagram;
Argon is in group 8A, this means it has eight valence electrons, so we draw Ar with 8 dots around it in its Lewis diagram;
Silicon is in group 4A, this means it has four valence electrons, so we draw Si with 4 dots around it in its Lewis diagram;
Arsenic is in group 5A, this means it has five valence electrons, so we draw As with 5 dots around it in its Lewis diagram.

Those are represented in the image attached below:

5 0

2 years ago