Explanation:
everything can be found in the picture
Answer:
The presence of dust on the victim's right or left hand
Explanation:
The presence of powder, the route of the bullet, and the damage the bullet generates tells us what the caliber of the weapon was like, and type.
The presence of gunpowder in the hand is a consequence of the person being shot, usually in the victim's skilled hand.
1) we calculate the molar mass of He (helium) and Kr (Krypton).
atomic mass (He)=4 u
atomic mas (Kr)=83.8 u
Therefore the molar mass will be:
molar mass(He)=4 g/mol
molar mass(Kr)=83.8 g/mol.
1) We can find the next equation:
mass=molar mass x number of moles.
x=number of moles of helium
y=number of moles of helium.
(4 g/mol) x +(83.8 g/mol)y=103.75 g
Therefore, we have the next equation:
(1)
4x+83.8y=103.75
2) We can find other equation:
We have 30% helium atoms and 70% Kryptum atoms, therefore we have 30% Helium moles and 70% of Krypton moles.
1 mol is always 6.022 * 10²³ atoms or molecules, (in this case atoms).
Then:
x=number of moles of helium
y=number of moles of helium.
(x+y)=number of moles of our sample.
x=30% of (x+y)
Therefore, we have this other equation:
(2)
x=0.3(x+y)
With the equations(1) and (2), we have the next system of equations:
4x+83.8y=103.75
x=0.3(x+y) ⇒ x=0.3x+0.3y ⇒ x-0.3x=0.3y ⇒ 0.7 x=0.3y ⇒ x=0.3y/0.7
⇒x=3y/7
We solve this system of equations by substitution method.
x=3y/7
4(3y/7)+83.8y=103.75
lower common multiple)7
12y+586.6y=726.25
598.6y=726.25
y=1.21
x=3y/7=3(1.21)/7=0.52
We have 0.52 moles of helium and 1.21 moles of Krypton.
1 mol=6.022 * 10²³ atoms
Total number of particles=(6.022 *10²³ atoms /1 mol) (number of moles of He+ number of moles of Kr).
Total number of particles=6.022 * 10²³ (0.52+1.21)=6.022 * 10²³ (1.73)=
=1.044 * 10²⁴ atoms.
Answer: The sample have 1.044 * 10²⁴ atoms.
Answer:
Metals at the top
nonmetals at the bottom
metalloids in the middle
Don't quote me, i could be wrong. i think this is the correct order.
Explanation:
The mass of 
that would be formed will be 18.22 grams
<h3>Stoichiometric calculations</h3>
Let us first look at the balanced equation of the reaction:
The mole ratio of Y to 
is 2:3.
Mole of 10.0 grams of Y = 10/88.9 = 0.11 moles
Mole of 10.0 grams = 10/71 = 0.14 moles
3/2 of 0.11 = 0.165. Thus, is limiting in availability.
Mole ratio of and = 3:2
Equivalent mole of = 2/3 x 0.14 = 0.093 moles.
Mass of 0.093 moles =0.093 x 195.26 = 18.22 grams
More on stoichiometric calculations can be found here: brainly.com/question/27287858
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