B, H2O + Na The elements toward the bottom left corner of the periodic table are the metals that are the most active in the sense of being the most reactive. Lithium, sodium, and potassium all react with water,

5 0

2 years ago

What is a good title for this chart?

Elina [12.6K]

Answer:

pH of the acid

Explanation:

8 0

2 years ago

A certain substance X has a normal freezing point of -6.4 C and a molal freezing point depression constant Kf= 3.96 degrees C.kg

Brut [27]

Answer: $1.0\times 10^2g$

Explanation:

Depression in freezing point is given by:

$\Delta T_f=i\times K_f\times m$

$\Delta T_f=T_f^0-T_f=(-6.4-(13.6))^0C=7.2^0C$ = Depression in freezing point

i= vant hoff factor = 1 (for non electrolyte like urea)

$K_f$ = freezing point constant = $3.96^0C/m$

m= molality

$\Delta T_f=i\times K_f\times \frac{\text{mass of solute}}{\text{molar mass of solute}}\times \text{weight of solvent in kg}}$

Weight of solvent (X)= 950 g = 0.95 kg

Molar mass of non electrolyte (urea) = 60.06 g/mol

Mass of non electrolyte (urea) added = ?

$7.2=1\times 3.96\times \frac{xg}{60.06 g/mol\times 0.95kg}$

$x=1.0\times 10^2g$

Thus $1.0\times 10^2g$ urea was dissolved.

8 0

3 years ago

How many uL are present in 250 mL of H20? (1 uL = 10^-6 Liters)

Vanyuwa [196]

Answer:

250000 μL

Explanation:

If 1 L = 1000 mL

Then X L = 250 mL

X = (1 × 250) / 1000 = 0.25 L

Now we can calculate the number of microliters (μL) in 0.25 L:

if 1 μL = 10⁻⁶ L

then X μL = 0.25 L

X = (1 × 0.25) / 10⁻⁶ =250000 μL

4 0

2 years ago