Simple Conversions

How many atoms are in 2 moles of carbon (MM = 12g/mol)? 

A substance has a molar mass of 32 g/mol. How many moles are in 0.96 grams of this substance?

How many moles of solute are present in 50 mL of 4M solution?

What is the total mass in grams of  3 × 10²³ atoms of magnesium (MM = 24 g/mol)? 

Researchers investigated the binding affinity of GPC-100, a novel CXCR4 antagonist, against the established inhibitor AMD3100 using a competitive binding assay.First CXCR4 terbium-labeled cells were plated in a 96-well format. To initiate competition, 5 μL of either GPC-100 or AMD3100 was added to each well, followed by 5 μL of a 20 nM red fluorescently labeled CXCL12 solution. The degree to which each compound displaced CXCL12 from CXCR4 was used as a measure of binding potency. After a 3-hour incubation at room temperature, fluorescence was measured.

Adapted from: Wenker SD, Farias MI, Gradaschi V, Garcia C, Beauquis J, Leal MC, et al. (2023) Microglia-secreted TNF-α affects differentiation efficiency and viability of pluripotent stem cell-derived human dopaminergic precursors. PLoS ONE 

During the competitive binding assay, how many moles of fluorescently labeled CXCL12 were added to each well? 

A substance has a density of 8 g/mL. What is the mass of 0.025 L of this substance?

How many molecules of water are present in 90 kg of water (MM = 18g/mol)?

MDA-MB-231 cells endogenously expressing CXCR4 and β2AR, or transduced with adenoviruses encoding CXCR4 for overexpression, were used for calcium flux assays. Cells were cultured for 2 days prior to running the assay and seeded at 8 × 10⁴ cells/well in a 96-well black clear-bottom microplate. The following day, cells were stained with Cal-520 AM for 2 hours at 37°C and treated with antagonists for 30 minutes, followed by agonist stimulation. Intracellular calcium flux was then measured.

What is the total number of cells seeded across the entire microplate in the calcium flux assay?

What total mass of NaCl in grams is dissolved in 2 liters of a 3 M NaCl solution (molar mass = 58.5 g/mol)?

Compound 1 (MM = 40 g/mol) is dissolved in 250 mL of solvent to form a 4 M solution. If the density of compound 1 is 2 g/mL what volume of dry compound 1 was dissolved in to make the solution?