I am from Pakistan , Gilgit- Baltistan . i am working as a lecturer for Chemistry for the last 4 years.
Estimate the angle to the nearest one-half radian.
A molecule with the formula AB3 has a trigonal planar geometry.How many electron groups are on the central atom?
Formula Mass and the Mole Concept for Compounds
Determine the number of moles (of molecules or formula units) ineach sample.$$\begin{array}{ll}{\text { a. } 55.98 \mathrm{g} \mathrm{CF}_{2} \mathrm{Cl}_{2}} & {\text { b. } 23.6 \mathrm{kg} \mathrm{Fe}\left(\mathrm{NO}_{3}\right)} \\ {\text { c. } 0.1187 \mathrm{g} \mathrm{C}_{8} \mathrm{H}_{18}} & {\text { d. } 195 \mathrm{kg} \mathrm{CaO}}\end{array}$$
How many molecules are in each sample?$$\begin{array}{ll}{\text { a. } 6.5 \mathrm{g} \mathrm{H}_{2} \mathrm{O}} & {\text { b. } 389 \mathrm{g} \mathrm{CBr}_{4}} \\ {\text { c. } 22.1 \mathrm{g} \mathrm{O}_{2}} & {\text { d. } 19.3 \mathrm{g} \mathrm{C}_{8} \mathrm{H}_{10}}\end{array}$$
How many molecules (or formula units) are in each sample?$$\begin{array}{lllll}{\text { a. } 85.26 \mathrm{gCCl}_{4}} & {\text { b. } 55.93 \mathrm{kg} \mathrm{NaHCO}_{3}} \\ {\mathrm{c} .119 .78 \mathrm{g} \mathrm{C}_{4} \mathrm{H}_{10}} & {\text { d. } 4.59 \times 10^{5} \mathrm{g} \mathrm{Na}_{3} \mathrm{PO}_{4}}\end{array}$$
Calculate the mass (in $g$ ) of each sample.$$\begin{array}{l}{\text { a. } 5.94 \times 10^{20} \mathrm{SO}_{3} \text { molecules }} \\ {\text { b. } 2.8 \times 10^{22} \mathrm{H}_{2} \mathrm{O} \text { molecules }} \\ {\text { c. } 1 \text { glucose molecule }\left(\mathrm{C}_{6} \mathrm{H}_{12} \mathrm{O}_{6}\right)}\end{array}$$
Which protein is a positive regulator that phosphorylates other proteins when activated?
1. p53
2. Retinoblastoma protein (Rb)
3. Cyclin
4. Cyclin-dependent kinase (Cdk)
Which of the following accounts are used when recording the sales entry of a sale on credit?
Working capital is an indication of the firm’s ________.
Use of drivers to assign costs to cost objects
