Explanation:
The equation of the reaction is given as;
Be + 2HCl → BeCl2 + H2
What is the mass of beryllium required to produce 25.0g of beryllium chloride?
1 mol of Be produces 1 mol of BeCl2
Converting to mass;
Mass = Molar mass * Number of moles
9.01g of Be produces 79.92g of BeCl2
xg of Be produces 25g of BeCl2
Solving for x;
x = 25 * 9.01 / 79.92
x = 2.82 g
What is the mass of hydrochloric acid required to produce 25.0g of beryllium chloride? g
Converting 25.0g of beryllium chloride to moles;
Number of moles = Mass / Molar mass
Number of moles = 25 / 79.92 = 0.3128 mol
2 mol of HCl produces 1 mol of BeCl2
x mol of HCl would produce 0.3128 mol of BeCl2
solving for x;
x = 0.3128 * 2 = 0.6256 mol
Converting to mass;
Mass = 0.6256 * 36.5 = 22.83 g
What is the mass of hydrogen gas produced when 25.0g of beryllium chloride is also produced? g
25g of BeCl2 = 0.3128 mol of BeCl2
From the equation;
1 mol of H2 is produced alongside 1 mol of BeCl2
This means;
0.3128 mol of H2 would also be produced alongside 0.3128 mol of BeCl2
Mass = Number of moles * Molar mass
Mass = 0.3128mol * 2.0159 g/mol = 0.6306 g
The answer is: " 1.75 * 10 ^(-10) m " .
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Explanation:
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This very question asked for "Question Number 3 (THREE) ONLY, which is fine!
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Given: " 0.000000000175 m " ; write this in "scientific notation.
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Note: After the "first zero and the decimal point" {Note: that first zero that PRECEDES the decimal point in merely a "placeholder" and does not count as a "digit" — for our purposes} —
There are NINE (9) zeros, followed by "175"
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To write in "scientific notation", we find the integer that is written, as well, as any "trailing zeros" (if there are any—and by "trailing zeros", this means any number consecutive zeros/and starting with "the consecutive zeros" only —whether forward (i.e., "zeros following"; or backward (i.e. "zeros preceding").
In our case we have "zeros preceding"; that is a decimal point with zeros PRECEDING an "integer expression"<span>
</span><span> (the "integer" is "175").</span>
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We then take the "integer expression" (whatever it may be: 12, 5, 30000001 ; or could be a negative value, etc.) ;
→ In our case, the "integer expression" is: "175" ;
and take the first digit (if the expression is negative, we take the negative value of that digit; if there is only ONE digit (positive or negative), then that is the digit we take ;
And write a decimal point after that first digit (unless in some cases, there is only one digit); and follow with the rest of the consecutive digits of that 'integer expression' ;
→ In our case: "175" ; becomes: " 1.75" .
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Then we write: " * 10^ "
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{that is "[times]"; or "multiplied by" : [10 raised exponentially to the power of <u> </u> ]._____________________________________________________
And to find that power, we take the "rewritten integer value (i.e. "whole number value that as been rewritten to a single digit with a decimal point"); and count the [number of "trailing zeros"; if there are any; PLUS the number of decimal places one goes] ; and that number is the value to which "10" is raised.
{If there are none, we write: " * 10⁰ " ; since "any value, raised to the "zero power", equals "1" ; so " * 10⁰ " ; is like writing: " * 1 " .
If there are "trailing zeros" AND/OR or any number of decimal places, to the "right" of this expression; the combined number of spaces to the right is:
{ the numeric value (i.e. positive number) of the power to which "10" is raised }.
Likewise, if there are "trailing zeros" AND/OR or any number of decimal places, to the "LEFT" of this expression; the combined number of spaces to the LEFT is the value of the power which "10" is raised to; is that number—which is a negative value.
In our case: we have: 0.000000000175 * 10^(-10) .
Note: The original notation was:
→ " 0.000000000175 m "
{that is: "175" [with 9 (nine) zeros to the left].}.
We rewrite the "175" ("integer expression") as:
"1.75" .
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So we have:
→ " 0.000000000175 m " ;
Think of this value as:
" 0. 0000000001{pseudo-decimal point}75 m ".
And count the number of decimal spaces "backward" from the
"pseudo-decimal point" to the actual decimal; and you will see that there are "10" spaces (to the left).
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Also note: We started with "9 (nine)" preceding "zeros" before the "1" ; now we are considering the "1" as an "additional digit" ;
→ "9 + 1 = 10" .
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Since the decimals (and zeros) come BEFORE (precede) the "175" ; that is, to the "left" of the "175" ; the exponent to which the "10" is raised is:
"NEGATIVE TEN" { "-10" } .
So we write this value as: " 1.75 * 10^(-10) m " .
{NOTE: Do not forget the units of measurement; which are "meters" —which can be abbreviateds as: "m" .} .
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The answer is: " 1.75 * 10^(-10) m " .
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Answer:
Rate = 0.001615 Ms-1
Explanation:
2 NO2 + F2 --> 2 NO2F
The reaction is first order with respect to NO2 and also first order with respect to F2.
The rate law is given as;
Rate = k [NO2] [ F2]
k = 1.58E-4 M-1s-1
[NO2] = 2.84 M
[F2] = 3.60 M
Rate = ?
Inserting the values into the equation, we have;
Rate = 1.58E-4 * 2.84 * 3.60
Rate = 0.001615 Ms-1
Answer:
Explanation:
Coinage metals -
The group 11 elements , i.e. , Copper , Silver , Gold are called the coinage metals .
These metals are quite soft and can be easily molded to form coins . This property is called as the property of malleability .
And due its soft nature , it can easily be used to make jewelry ,
Since , making jewels require the metal to be soft and flexible ,
Hence , gold is suited the best for this .
Principle quantum number describes the energy of an electron and most probable distance of the electron from the nucleus.
<h3>What is the significance of principle quantum numbers and azimuthal quantum numbers?</h3>
A principal quantum number signifies size and energy of the orbital.Azimuthal quantum number signifies three dimensional shape of the orbital.
Magnetic quantum numbers signifies spatial orientation of the orbital.
Principal quantum numbers is the quantum numbers denoted by n which indirectly describes the size of the electron orbitals. It is always assigned an integer value but its value never be 0. The feature of a principal quantum numbers is the energy of an electron and most probable distance of the electron from the nucles.
to learn more about Principal quantum numbers click here brainly.com/question/16979660
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