Which of the following statements is false? molecules with the formulas ch3ch2cooh and c3h6o2 could be structural isomers. molecules must have a double bond to be cis-trans isomers. to be enantiomers, a molecule must have at least three different atoms or groups connected to a central carbon. to be enantiomers, a molecule must have at least four different atoms or groups connected to a central carbon.

To be enantiomers, a molecule must have at least three different atoms or groups connected to a central carbon.

Explanation:

To be structural isomers, the molecules must have the same formula and different structure, it means, the same number of each element. CH3CH2COOH and C3H6O2 have 3C, 6H, and 2O, so they can be structural isomers.

Cis-trans isomers occur in molecules with a double bond between carbons, and each carbon has to have 2 different atoms or groups connected to it.

Enantiomers are optic isomers, and to occur, the molecule has to have a chiral carbon (an asymmetric carbon), which is a central carbon connected to four different atoms or groups. So the third affirmative is false because it says that is necessary only three different atoms or groups connected to a central carbon.

you need to take a look at the periodic system in order to sort these elements into pairs that would most likely exhibit similar chemical properties. first, you need to find elements that are found in the same group (groups are vertical in the periodic system), and then to see whether they have the same valence number. if they meet these criteria, they will have similar properties.

the first pair: ne (neon) and kr (krypton), are noble gases found in group 8

the second pair: li (lithium) and k (potassium), found in group 1

the third pair: s (sulfur) and te (tellurium), found in group 6

no, the red giant is the hottest with 2.00.000.000 degrees celsius. while the white dwarf only 25,000 degrees celsius.