All of the elements below can exist as network solids EXCEPT 1. As 2. B 3. Si 4. O 5. C

Kamila [148]

Answer:

SiF4 is not a polar covalent bond.

Explanation:

SiF4 is a nonpolar molecule because the fluorine's are arranged around the central silicon atom in a tetrahedral molecule with all of the regions of negative charge cancelling each other out.

8 0

3 years ago

What do butterflies and lobsters have in common?

Stella [2.4K]

Answer:

They all wear their skeletons on the outside! This is called an exoskeleton and all creatures that have their structure on the outside are included in the phylum of Arthropods.

Explanation:

3 0

3 years ago

On a summer day, you take a road trip through Chelan, WA, in a Tesla Model S. You start out at a temperature of 19°C in the morn

ASHA 777 [7]

1. 1.636 moles

2. 271.06 kPa pressure

3. Tires will be burst

4. 235.91 kPa

Explanation:

Step 1:

PV = nRT, is the equation to be used where

P represents pressure

V represents volume

n represents moles of gas

R is constant

T represents temperature in Kelvin

n=RT/PV

It is given that the pressure is 245 kPa at initial temperature 19 C and tire volume is 16.2 L. Temperature must be converted to Kelvin, 19 C equals 292K.

n=PV/RT ->245*16.2/(8.31*292) = 1.636

Number of moles of Nitrogen in the tire = 1.636

Step 2:

We need to find the maximum tire pressure at 50 C (323K)

P = nRT/V

Substituting the values P = (1.636 * 8.31 * 323)/16.2 = 271.06 kPa

The tire pressure at 50 C will be 271.06 kPa

Step 3

We need to figure out if the tires would burst in Chelan when the temperature is 55 C. It is given that the maximum pressure the tires can withstand is 265 kPA, so any pressure above this will cause the tire to burst. In Step-2 we calculated that the pressure is 271.06 kPA at 50 C which is more than the maximum pressure the tire can withstand. The pressure would increase further with temperature and at 55 C the pressure will be more than 271.06 kPa. So the tires are likely to burst in Chelan.

Step 4:

We need to find the pressure of Nitrogen at 19 C before the start of the trip so that tires will not burst. The pressure at 55 C is 265 kPa. Let us find the number of moles at this temperature and pressure.

n= PV/RT -> n=265*16.2/(8.31*328) = 1.575

Now let us find the pressure at 19 C.

P = nRT/V -> 1.575*8.31*292/16.2 = 235.91 kPa

8 0

3 years ago

In an acid-base titration, a student uses 21.35 mL of 0.150 M NaOH to neutralize 25.00 mL of H2SO4. How many moles of acid are i

GalinKa [24]

Answer: There are 0.006 moles of acid in the flask.

Explanation:

Given: $V_{1}$ = 21.35 mL, $M_{1}$ = 0.150 M

$V_{2}$ = 25.0 mL, $M_{2}$ = ?

Formula used to calculate molarity of $H_{2}SO_{4}$ is as follows.

$M_{1}V_{1} = M_{2}V_{2}$

Substitute the values into above formula as follows.

$M_{1}V_{1} = M_{2}V_{2}\\0.15 M \times 21.35 mL = M_{2} \times 25.0 mL\\M_{2} = 0.1281 M$

As molarity is the number of moles of a substance present in a liter of solution.

Total volume of solution = $V_{1} + V_{2}$

= 21.35 mL + 25.0 mL

= 46.36 mL (1 mL = 0.001 L)

= 0.04636 L

Therefore, moles of acid required are calculated as follows.

$Molarity = \frac{no. of moles}{Volume (in L)}\\0.1281 M = \frac{no. of moles}{0.04635 L}\\no. of moles = 0.006 mol$

Thus, we can conclude that there are 0.006 moles of acid in the flask.

3 0

3 years ago

Decide whether a chemical reaction happens in either of the following situations. If a reaction does happen, write the chemical

ValentinkaMS [17]

Answer:

1) Yes

2) No

Explanation:

A strip of solid magnesium metal is put into a beaker of 0.053M ZnSO4 solution-YES

A chemical reaction occurs

Mg(s) + ZnSO4(aq) ----------> MgSO4(aq) +Zn(s)

This reaction is possible because magnesium is far higher than zinc in the activity series of metals hence magnesium can displace zinc from a solution of a zinc salt.

A strip of solid zinc metal is put into a beaker of 0.058M MgBr2 solution. NO

A chemical reaction does not occur because magnesium is higher than zinc in the activity series hence zinc cannot displace magnesium from a solution of its salt.

8 0

3 years ago