Answer: a. Have an overall neutral charge
b. Have electrons that are not equally shared
d. Have slight positive and negative ends
Explanation:
Electronegativity is defined as the property of an element to attract a shared pair of electron towards itself.
A polar covalent bond is defined as the bond which is formed when there is a difference of electronegativities between the atoms. Example: 
The more electronegative element i.e. chlorine acquires a partial negative charge as it withdraws the electron density towards itself. Thus hydrogen acquires a partial positive charge. The opposite charges cancel each other and thus overall it is electrically neutral.
Answer: the cake rises as gas bubbles form in the cake
Explanation: Had a quizziz quiz on this
6.11% w/v of Cu2+ implies that 6.11 g of Cu2+ is present in 100 ml of the solution
therefore, 250 ml of the solution would have: 250 ml * 6.11 g/100 ml = 15.275 g
# moles of Cu2+ = 15.275 g/63.546 g mole-1 = 0.2404 moles
1 mole of CuCl2 contain 1 mole of Cu2+ ion
Hence, 0.2404 moles of Cu2+ would correspond to 0.2404 moles of CuCl2
Molar mass of CuCl2 = 134.452 g/mole
The mass of CuCl2 required = 0.2404 moles * 134.452 g/mole = 32.32 grams
NaCl:
Na = + 1
Cl = - 1
hope this helps!