Answer:
Cyclopropane has a planar carbon back bone while propane does not
Explanation:
We have to recognize that in straight chain saturated organic compounds, carbon atoms have a tetrahedral geometry. Each carbon atom is bonded to four other atoms.
However, carbon atoms in cyclic compounds are also sp3 hybridized with each carbon bonded to only four other atoms but the ring system is highly strained.
Cyclopropane is a necessarily planar molecule with a bond angle that is far less than the expected tetrahedral bond angle due to strain in the molecule. Hence, the carbon atoms may have have a "planar backbone".
I believe that it is a chemical change.
Correct Answer: Option B: <span>whether the particles do not settle for an extended period of time
Reason:
Particle size in colloidal solution ranges from 1-100 nm, while that is suspension is more than 100 nm. Due to large particle size, particles in suspension settle down, upon standing for long. Thus, the best </span>criteria determine whether a heterogeneous mixture is a colloid or a suspension is to check <span>whether the particles do not settle for an extended period of time</span>
Answer:
Difference of the enthalpy (of a system) minus the product of the entropy and absolute temperature
Explanation:
The basis of spontaneity in a chemical reaction is that ∆G must be negative. ¡∆G is known as the change in free energy of a system. If ∆G is negative, then the reaction will occur without any external help (the reaction is spontaneous at room temperature).
∆G is given by;
∆G= ∆H -T∆S
Where;
∆H= change in enthalpy of the system
T= absolute temperature of the system
∆S= change in entropy
Hence; when ∆H -T∆S gives a negative result, the reaction proceeds without any external help.
Answer;
D. Formation of NADPH
Explanation;
During the process of photosynthesis light is converted to chemical energy.
During stage 1, Excited electrons that leave the chlorophyll pigments in stage 1 are used. Excited electrons are passed through proteins in the thylakoid membrane like a ball being passed from person to person. H2o molecules split and turn into H+ molecules and O2 gas, then pigments take the electrons from the split water molecules and release O2 into the atmosphere.
During stage 2; electrons from 1st cluster pump H+ ions into the thylakoid membrane through the hydrogen ion pump (protein membrane. Higher concentration of H+ ions inside the thylakoid membrane compared to outside. H+ ions diffuse out of the thylakoid throught the ATP synthase (enzyme in membrane). ATP synthase catalyzes the reaction ADP + P ---->ATP.
Stage 2; Excited electrons + H+ ions + NADP+= NADPH
