It is energetically favorable for all atoms to have a complete outer
electron shell. Loosely, the atoms on the left hand side of the periodic
table only have a few extra electrons in their outer shell so it is
energetically favorable for them to lose them. The atoms on the right
hand side of the periodic table almost have enough electrons in their
outer shell and so they have a tendency to gain them.
Once electrons have left an electron shell, an atom will have a positive
charge because it has more protons (positive charges) than electrons
(negative charges). Similarly, an electron which has gained electrons to
complete its outer shell will have a negative charge because it now has
more electrons (negative charge) than protons (positive charge).
Answer:
- 130.64°C.
Explanation:
- We can use the general law of ideal gas:<em> PV = nRT.</em>
where, P is the pressure of the gas in atm.
V is the volume of the gas in L.
n is the no. of moles of the gas in mol.
R is the general gas constant,
T is the temperature of the gas in K.
- If n and P are constant, and have two different values of V and T:
<em>V₁T₂ = V₂T₁</em>
<em></em>
V₁ = 634.0 L, T₁ = 21.0°C + 273 = 294.0 K.
V₂ = 307.0 L, T₂ = ??? K.
<em>∴ T₂ = V₂T₁/V₁ </em>= (307.0 L)(294.0 K)/(634.0 L) = <em>142.36 K.</em>
<em>∴ T₂(°C) = 142.36 K - 273 = - 130.64°C.</em>
Hey there!:
From the given data ;
Reaction volume = 1 mL , enzyme content = 10 ug ( 5 ug in 2 mg/mL )
Enzyme mol Wt = 45,000 , therefore [E]t is 10 ug/mL , this need to be express as "M" So:
[E]t in molar = g/L * mol/g
[E]t = 0.01 g/L * 1 / 45,000
[E]t = 2.22*10⁻⁷
Vmax = 0.758 umole/min/ per mL
= 758 mmole/L/min
=758000 mole/L/min => 758000 M
Therefore :
Kcat = Vmax/ [E]t
Kcat = 758000 / 2.2*10⁻⁷ M
Kcat = 3.41441 *10¹² / min
Kcat = 3.41441*10¹² / 60 per sec
Kcat = 5.7*10¹⁰ s⁻¹
Hence kcat of xyzase is 5.7*10¹⁰ s⁻¹
Hope that helps!
Answer:
a) 
b) 
c) 
Explanation:
The symbols of the isotopes are written like

where,
X is the element
A is the mass number (protons + neutrons)
Z is the atomic number (protons)
<em>a) Iodine-131</em>
The atomic number of iodine is 53. The mass number of this isotope is 131. The symbol is
.
<em>b) Iridium-192</em>
The atomic number of iridium is 77. The mass number of this isotope is 192. The symbol is
.
<em>c) Samarium-153</em>
The atomic number of samarium is 62. The mass number of this isotope is 153. The symbol is
.