For a concave mirror, incident light beams through C will reflect:

Which technique can be used to remove air bubbles from a syringe? a) Hold the syringe downward, shake vigorously for 10 seconds,

swat32

hold the syringe downward,shake vigorously for sometime,and expel the bubbles through the needle using the syringe plunger. hold the syringe upright, provide a firm tap or flick to the barrel

3 0

2 years ago

Changing atmospheric conditions, like increasing carbon dioxide content, might possibly _____.

kobusy [5.1K]

<span>Changing atmospheric conditions, like increasing carbon dioxide content, might possibly increase the risk of global warming. Carbon dioxide, along with other greenhouse gases, is one of the leading causes of our Earth's rise in temperature. This is because greenhouse gases trap the planet's heat inside its atmosphere, preventing it from leaving the Earth's surface. </span>

5 0

4 years ago

How do you know what atoms are convalant or ionic

Paha777 [63]

ionic bond is formed when two oppositely charged ions attract one another.A covalent bond, also called a molecular bond, is a chemical bond that involves the sharing of electron pairs between atoms.

7 0

3 years ago

Adding which of the following substances will decrease the solubility of calcium chloride in water: CaCl2(s) Ca2+(aq) + 2 Cl–(aq

Korvikt [17]

Answer:

Option b. Sodium chloride.

Explanation:

Consider the dissociation equilibrium of $\rm CaCl_2 \; (s)$ in water:

$\rm CaCl_2 \; (s) \rightleftharpoons Ca^{2+} \; (aq) + 2\; Cl^{-}\; (aq)$ .

By the Le Chatelier's Principle, increasing the concentration of either product will shift the equilibrium to the left. Some $\rm CaCl_2 \; (s)$ that was initially dissolved will precipitate out of the solution. This effect is called the common-ion effect.

For this $\rm CaCl_2 \; (s)$ solution, the products of dissociation are

$\rm Ca^{2+}$ ions, and
$\rm Cl^{-}$ ions.

Adding either to the solution will trigger the common-ion effect and reduce the solubility of $\rm CaCl_2 \; (s)$ .

In the two choices,

Sodium chloride $\rm NaCl$ will add $\rm Na^{+}$ and $\rm Cl^{-}$ ions to the solution.
Sodium fluoride $\rm NaF$ will add $\rm Na^{+}$ and $\rm F^{-}$ ions to the solution.

$\rm NaCl$ contains $\rm Cl^{-}$ ions. It is capable of triggering the common-ion effect. However $\rm NaF$ contains neither $\rm Ca^{2+}$ ions nor $\rm Cl^{-}$ ions. It will not trigger the common-ion effect.

6 0

3 years ago

What would you predict about a chemical that has a hydrogen ion concentration of 1×10 to the -12 power M

boyakko [2]

You can predict its acidity (pH).

The formula for pH is: pH = log { 1 / [H+] } = log { 1 / (1*10^-12) }

=> pH = log {10^12} = 12.

Remember that acids have pH between 1 and less than 7 and basic compounds have pH greater than 7 and less than 14.

So, you can predict that this product is a base (alkaline).

7 0

3 years ago