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Len [333]
4 years ago
5

When heating test tubes, always slant them away from yourself and others. True False

Chemistry
1 answer:
Leni [432]4 years ago
3 0

Answer:

true

Explanation:

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Use the reaction N2(g) + 3H2(g) 2NH3(g) to answer the following questions
densk [106]

Answer:

cvbn

Explanation:

5 0
3 years ago
Determine the energy of the electron in the 1s orbital of a helium ion (He+ )
Luda [366]
He Rydberg formula can be extended for use with any hydrogen-like chemical elements. 
<span>1/ λ = R*Z^2 [ 1/n1^2 - 1/n2^2] </span>
<span>where </span>
<span>λ is the wavelength of the light emitted in vacuum; </span>
<span>R is the Rydberg constant for this element; R 1.09737x 10^7 m-1 </span>
<span>Z is the atomic number, for He, Z =2; </span>
<span>n1 and n2 are integers such that n1 < n2 </span>
<span>The energy of a He+ 1s orbital is the opposite to the energy needed to ionize the electron that is </span>
<span>taking it from n = 1 (1/n1^2 =1) to n2 = ∞ (1/n2^2 = 0) </span>
<span>.: 1/ λ = R*Z^2 = 1.09737x 10^7*(2)^2 </span>
<span>λ = 2.278*10^-8 m </span>
<span>E = h*c/λ </span>
<span>Planck constant h = 6.626x10^-34 J s </span>
<span>c = speed of light = 2.998 x 10^8 m s-1 </span>
<span>E = (6.626x10^-34*2.998 x 10^8)/(2.278*10^-8) = 8.72*10^-18 J ion-1 </span>
<span>Can convert this value to kJ mol-1: </span>
<span>(8.72*10^-18*6.022 x 10^23)/1*10^3 = 5251 kJ mol-1 </span>
<span>Lit value: RP’s secret book: 5240.4 kJ mol-1 (difference is due to a small change in R going from H to He+) </span>
<span>So energy of the 1s e- in He+ = -5251 kJ mol-1</span>
6 0
3 years ago
Phosphoric acid reacts with magnesium hydroxide to produce magnesium phosphate and water via the following reaction: ?H3PO4+?Mg(
natulia [17]
Please note that since magnesium is in group 2 it has a valency of 2+ and so the formula for magnesium hydroxide is
M
g
(
O
H
)
2
[Mistake in question]
This is a typical neutralization reaction of an acid with a base to form a salt and water. The reaction is exothermic, gives off heat,
Δ
H
<
0
, and may be balanced by adding balancing numbers in front, ie adding molecules, in order to ensure that the total number of atoms of each element is the same on the left and right hand sides of the equation.
Doing so we obtain :
2
H
3
P
O
4
+
3
M
g
(
O
H
)
2
→
M
g
3
(
P
O
4
)
2
+
6
H
2
O
4 0
3 years ago
Which option identifies why Tony does NOT purchase the strawberries in the following scenario?
trapecia [35]

Answer:

He only purchases strawberries grown locally.

Explanation:

Based on the information we are given, this is the only reasonable answer.

3 0
3 years ago
Read 2 more answers
What is an orbital????
kherson [118]

Answer:

Orbital, in chemistry and physics, a mathematical expression, called a wave function, that describes properties characteristic of no more than two electrons in the vicinity of an atomic nucleus or of a system of nuclei as in a molecule. ... A 1s electron occupies the energy level nearest the nucleus.

Explanation:

3 0
3 years ago
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