Answer:
Substances 1 and 2
Explanation:
an element only has 1 kind of atoms :3
Seeds, because angiosperms seeds are in flowers.
Answer:
The cohesive forces of mercury are much stronger than its adhesive forces.
Explanation:
Cohesive forces are forces that exist between the particles that compose a substance while adhesive forces refer to forces that exist between the particles of a substance and those of another substance.
The cohesive forces in mercury far outweigh the adhesive forces between the mercury drops and glass. Hence when mercury is put into a capillary tube, its meniscus is convex because cohesive forces tend to draw the liquid mercury into a drop.
Hence, the surface tension in mercury makes the mercury in the capillary tube to fall below the height of the mercury in the dish.
Answer:
99.24%.
Explanation:
- NaCl reacted with AgNO₃ as in the balanced equation:
<em>NaCl + AgNO₃ → AgCl(↓) + NaNO₃,</em>
1.0 mol of NaCl reacts with 1.0 mol of AgNO₃ to produce 1.0 mol of AgCl and 1.0 mol of NaNO₃.
- We need to calculate the no. of moles of AgCl produced:
no. of moles of AgCl = mass/molar mass = (2.044 g)/(143.32 g/mol) = 0.0143 mol.
- Now, we can calculate the no. of moles of NaCl that can precipitated as AgCl (0.0143 mol), these moles represents the no. of moles of pure NaCl in the sample:
<em>using cross multiplication:</em>
1.0 mol of NaCl produce → 1.0 mol of AgCl, from the stichiometry.
∴ 0.0143 mol of NaCl produce → 0.0143 mol of AgCl.
- Now, we can get the mass of puree NaCl in the sample:
mass of pure NaCl = (no. of moles of pure NaCl)(molar mass of NaCl) = (0.0143 mol)(58.44 g/mol) = 0.8357 g.
∴ The percentage of NaCl in the impure sample = [(mass of pure NaCl)/(mass of the impure sample)] x 100 = [(0.8357 g)/(0.8421 g)] x 100 = 99.24%.
The relationship between volume and pressure is described in the Gay-Lussac's law. That is,
P₁V₁ = P₂V₂
Substituting the known values,
(75 mL)(145 atm) = (500 mL)(P₂)
The value of P₂ is equal to 21.75 atm.