Answer:
26. Hemoglobin is a tetramer that consists of four polypeptide chains. Each monomer contains a heme group in which an iron ion is bound to oxygen.
Explanation:
Answer:
A.
Explanation:
Manganese (Mn) is a silver-colored metal. It reacts with oxygen to form manganese oxide (MnO2), which has two oxygen atoms for every manganese atom. Which statement describes the properties of manganese oxide? It will be a gas because there are more oxygen atoms.
In 0.25 mole there are 1.5*1023 molecules of 02 since there are 6.02*1023 particles in one mole.
Answer:
75 kJ/mol
Explanation:
The reactions occur at a rate, which means that the concentration of the reagents decays at a time. The rate law is a function of the concentrations and of the rate constant (k) which depends on the temperature of the reaction.
The activation energy (Ea) is the minimum energy that the reagents must have so the reaction will happen. The rate constant is related to the activation energy by the Arrhenius equation:
ln(k) = ln(A) -Ea/RT
Where A is a constant of the reaction, which doesn't depend on the temperature, R is the gas constant (8.314 J/mol.K), and T is the temperature. So, for two different temperatures, if we make the difference between the two equations:
ln(k1) - ln(k2) = ln(A) - Ea/RT1 - ln(A) + Ea/RT2
ln (k1/k2) = (Ea/R)*(1/T2 - 1/T1)
k1 = 8.3x10⁸, T1 = 142.0°C = 415 K
k2 = 6.9x10⁶, T2 = 67.0°C = 340 K
ln(8.3x10⁸/6.9x10⁶) = (Ea/8.314)*(1/340 - 1/415)
4.8 = 6.39x10⁻⁵Ea
Ea = 75078 J/mol
Ea = 75 kJ/mol
Answer:
nonpolar covalent
Explanation:
Comparing their electronegativities will help determine the type of bond. Electronegativity is a measure of the tendency of an atom to attract a bonding pair of electrons. The difference in electronegativity (ΔEN) is used to determine bond type. Hydrogen has an electronegativity of 2.20 and sulfur has 2.58. The difference is 0.38,so the electrons are shared in a nonpolar covalent bond.
