Answer:
if we're talking about beryllium then the answer should be 2 because it wants to move 2 spaces back (losing electrons) to become a Nobel gas so the answer is 2+
Explanation:
it has 2 valence electrons YW :)
Answer:
1.58x10⁻⁵
2.51x10⁻⁸
0.0126
63.10
Explanation:
Phenolphthalein acts like a weak acid, so in aqueous solution, it has an acid form HIn, and the conjugate base In-, and the pH of it can be calculated by the Handerson-Halsebach equation:
pH = pKa + log[In-]/[HIn]
pKa = -logKa, and Ka is the equilibrium constant of the dissociation of the acid. [X] is the concentrantion of X. Thus,
i) pH = 4.9
4.9 = 9.7 + log[In-]/[HIn]
log[In-]/[HIn] = - 4.8
[In-]/[HIn] =
[In-]/[HIn] = 1.58x10⁻⁵
ii) pH = 2.1
2.1 = 9.7 + log[In-]/[HIn]
log[In-]/[HIn] = -7.6
[In-]/[HIn] =
[In-]/[HIn] = 2.51x10⁻⁸
iii) pH = 7.8
7.8 = 9.7 + log[In-]/[HIn]
log[In-]/[HIn] = -1.9
[In-]/[HIn] =
[In-]/[HIn] = 0.0126
iv) pH = 11.5
11.5 = 9.7 + log[In-]/[HIn]
log[In-]/[HIn] = 1.8
[In-]/[HIn] =
[In-]/[HIn] = 63.10
Answer:
Final temperature = 22.21 °C
Explanation:
Heat gain by ethanol = Heat lost by water
Thus,
Where, negative sign signifies heat loss
Or,
<u>For ethanol:
</u>
Density = 0.789 g/mL
Volume = 55.0 mL
Considering the expression for density as:
So,
So, Mass= Density*Volume = 0.789 g/mL * 55.0 mL = 43.395 g
Initial temperature = 9.0 °C
Specific heat of ethanol = 2.57 J/g°C
<u>For water:
</u>
Density = 1.0 g/mL
Volume = 55.0 mL
Considering the expression for density as:
So,
So, Mass= Density*Volume = 1.0 g/mL * 55.0 mL = 55.0 g
Initial temperature = 28.6 °C
Specific heat of water = 0.450 J/g°C
So,
<u>Final temperature = 22.21 °C </u>
I think that the answer is going to be D air pressure or A the muscles attached to the ribs
The molar mass of the protein is 45095 g/mol.
The mass of a sample of a chemical compound divided by the quantity, or number of moles in the sample, measured in moles, is known as the molar mass of that compound.
The expression of molar mass of protein is
M₂ = (W₂/P) (RT/V)
Given;
W₂ = 1.31g
P = 4.32 torr = 5.75 X 10⁻³ bar
R = 0.083 Lbar/mol/K
T = 25°C = 298.15 K
V = 125 ml = 0.125 L
Putting all the values in the above formula
M₂= (1.31 g/5.75 X 10⁻³ bar) X (0.083 Lbar/mol/K X 2)/0.125 L)
M₂ = 45095 g/mol
Thus, the molar mass of the protein is 45095 g/mol.
Learn more about the Molar mass with the help of the given link:
brainly.com/question/22997914
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