A few drops of Lugol's iodine solution placed in a beaker of water will turn the water red. A white starch solution was poured into a length of dialysis tubing and the ends were tied. The tubing was then dropped into the beaker of iodine solution. After 10 minutes, the white starch solution turned black, and the iodine water remained red. Why is the iodine able to go into the tubing, but the starch is not able to fall out of the tubing

gravity causes stares to cluster i think so

- calcium has greater affinity to bond with electron receptors than hydrogen does and hence, it has the ability to replace hydrogen in most of its compounds.

- lithium has 2 valence electrons in the product because it can make only 1 bond with hydrogen. beryllium has 4 valence electrons in the product because it can only make 2 bonds. it has fewer electrons than neon and can react with electron donors. each hydrogen has 2 valence electrons, the same as helium.

- the covalent bond formed between carbon and hydrogen is polar because carbon is more electronegative than hydrogen and it attracts the bonded electron pair closer to itself, thus giving hydrogen a partial positive charge.

- a hydrogen bond is a relatively weak bond that hydrogen atoms make with the electronegative atoms nitrogen, oxygen or fluorine.

so the best choice is a.) 2 calcium (ca) atoms

a) the particles of the chair are strongly held together.