Answer:
D
Explanation:
total mass should be equal on both sides
it's a double do displacement reaction
HCl + NaOH --> NaCl + H2O
How many grams of carbon dioxide does a hummingbird emit daily?
Answer:
3.5 g CO2
Explanation:
A hummingbird emits up to 3.5 grams of CO2 a day.
Equation:7.9 x 10‒2mol CO2x (44.01 g CO2/ 1 mol CO2)
=3.5 grams
Hope this helps!
PLEASE HELP!
Why is phosphorus diamagnetic.
Answer:
FROM the magnetic point of view, phosphorus is an extremely interesting
substance because of its allotropic modifications. The ordinary forms are
the yellow (or white) and the red varieties. X-ray investigations indicate
that probably yellow phosphorus is analogous with the cubic forms of antimony and arsenic; and red phosphorus with monoclinic antimony and
arsenic (Mellor, 1928). The conclusions of different workers on the structure of red phosphorus are not in agreement. There is also Bridgman's black
phosphorus which is probably hexagonal (Linck and lung, 1925). Natta
and Passerini (1930) have studied the crystal structure of white phosphorus.
This substance when condensed at the temperature of liquid ammonia is
cubic. Atomic positions however are yet undetermined. Another and noncubic form is obtained by condensation at liquid-air temperatures. It is
thus clear that most likely white phosphorus is cubic in structure with a
probable superposition of another lattice.
The evidence from Raman effect also points to the same conclusion.
Bhagavantam (1930) investigated the Raman effect of white phosphorus in
the solid state. The characteristic frequencies obtained by him are 607, 468
and 374. Since the phosphorus molecule is known to contain 4 atoms,
Bhagavantam (1930) has shown that the tetrahedral structure fits the results
satisfactorily since such a structure would give only three frequencies. But
for the particular law of forces adopted, the frequencies should have the
ratio 2: 2: 1 but the observed frequencies deviate considerably.
Phosphorus is a really intriguing element. because of the allotropic changes to the material.
Why phosphorus is dimagnetic?Red phosphorus is likely akin to monoclinic antimony, while yellow phosphorus is probably similar to the cubic forms of antimony and arsenic.
There is disagreement among the findings of many researchers regarding the structure of red phosphorus. Additionally, Bridgman's black It is presumably hexagonal, phosphorous (Linck and lung, 1925). Natta and Passerini (1930) have investigated the white phosphorus crystal structure.
Condensed from this material at liquid ammonia temperature is cubic. However, the locations of the atoms are still unknown. Condensation at liquid air temperatures yields a different, noncubic shape.
Therefore, Phosphorus is a really intriguing element. because of the allotropic changes to the material.
To learn more about phosphorus, refer to the link:
https://brainly.com/question/4622631
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14.
Two jewelers were asked to measure the
mass of a gold nugget. The true mass of the
nugget is 0.856 grams (g). Each jeweler took
three measurements. The average of the
three measurements was reported as the
"official” measurement with the following
results:
Jeweler A: 0.863 g, 0.869 g, 0.859 g
Jeweler B: 0.875 g, 0.834 g, 0.858 g
Which jeweler's official measurement was
more accurate? Which jeweler's measure-
ments were more precise? In each case, what
was the error and percent error in the official
measurement?
Answer:
Jeweler B = more accurate
Jeweler A = more precise
Error:
0.008, 0
% error :
0.934% ; 0
Explanation:
Given that:
True mass of nugget = 0.856
Jeweler A: 0.863 g, 0.869 g, 0.859 g
Jeweler B: 0.875 g, 0.834 g, 0.858 g
Official measurement (A) = 0.863 + 0.869 + 0.859 = 2.591 / 3 = 0.864
Official measurement (B) = 0.875 + 0.834 + 0.858 = 2.567 / 3 = 0.8556
Accuracy = closeness of a measurement to the true value
Accuracy = true value - official measurement
Jeweler A's accuracy :
0.856 - 0.864 = - 0.008
Jeweler B's accuracy :
0.856 - 0.856 = 0.00
Therefore, Jeweler B's official measurement is more accurate as it is more close to the true value of the gold nugget.
However, Jeweler A's official measurement is more precise as each Jeweler A's measurement are closer to one another than Jeweler B's measurement which are more spread out.
Error:
Jeweler A's error :
0.864 - 0.856 = 0.008
% error =( error / true value) × 100
% error = (0.008/0.856) × 100% = 0.934%
Jeweler B's error :
0.856 - 0.856 = 0 ( since the official measurement as been rounded to match the decimal representation of the true value)
% error = 0%
How many molecules are in each sample?
A. 4.9 g H2O
B. 54.4 g N^2
C. 89 g CCI4
D. 11 g C6H12O6
Answer:
To find the number of molecules first find the number of moles.
number of moles (n) = mass / molar mass (M)
then use the formula
N = n × L
where n = number of moles
N = number of entities
L = Avogadro's constant = 6.02 × 10^23entities to find the number of molecules
A. 4.9 g H2O
m = 4.9g
M = (2*1)+(16×1) = 2 + 16 = 18g/mol
n = 4.9/18 = 0.272mol
N = 0.272 × 6.02 × 10^23
= 1.6374*10^23 molecules of H2O
B. 54.4g of N2
m = 54.4g
M(N2) = 14×2 = 28g/mol
n = 54.4/28 = 1.942mol
N = 1.942 * 6.02*10^23
= 1.1690*10^24 molecules of N2
C. 89 g CCI4
m = 89g
M(CCl4) = 12 + (35.5 × 4) = 154g/mol
n = 89/154 = 0.577mol
N = 0.577 × 6.02 × 10^23
= 3.473*10^23 molecules of CCl4
D. 11 g C6H12O6
m = 11g
M(C6H12O6) = (12×6)+(12×1)+(16×6) =
180g/mol
n = 11/180 = 0.0611mol
N = 0.0611 × 6.02×10^23
= 3.678*10^22 molecules of C6H12O6
Hope this helps