How many moles of copper are in a 0.53 gram sample?

8.3 × 10⁻³ mol Cu

Explanation:

Step 1: Define

Molar Mass of Cu - 63.55 g/mol

Given 0.53 g Cu

Step 2: Use Dimensional Analysis

= 0.00834 mol Cu

Step 3: Convert

0.00834 mol Cu = 8.34 × 10⁻³ mol Cu

Step 4: Simplify

We are given 2 sig figs.

8.34 × 10⁻³ mol Cu ≈ 8.3 × 10⁻³ mol Cu

the best answer is d because the strong cohesion is caused by the ability of water molecules to undergo hydrogen bonding.

a is incorrect because when water solidifies, it becomes   ice, which expands and occupies a bigger volume for the same mass of water in its liquid state.

b is incorrect because water has high surface tension. besides bonding to itself it hydrogen bonds to other molecules at the top decreasing possibility for breaking of attractive forces.

c is incorrect because the water molecule has oxygen which is highly electronegative and so pulls the electron pair towards itself creating a dipole moment, making the molecule polar.

e is incorrect because water has strong adhesion, ability to stick to other molecules such as glass because of this molecules having stronger hydrogen bonding than water.

the correct answer is:

a. formation of precipitation