Complete the symbol equation for the preparation of sodium sulfate

Which body system provides protection of the brain and the spinal cord?

gogolik [260]

Answer:

The bones of the skull and spinal column

Explanation:

The central nervous system is better protected than any other system or organ in the body. Its main line of defense is the bones of the skull and spinal column, which create a hard physical barrier to injury.

8 0

3 years ago

Read 2 more answers

In a certain city, electricity costs $0.17 per kW·h. What is the annual cost for electricity to power a lamp-post for 5.50 hours

Anon25 [30]

Answer:

(a) = $34.123

(b) = $8.532

(c) Additional cost of fluorescent bulb is justified

Explanation:

Cost of electricity = $0.17 per kW·h

(a) For a 100 watt bulb which is the same as 100/1000 or 0.1 kW, the cost per hour =

0.1 × 0.17 = $0.017/h

and for 5.5 hours = 0.017×5.5 = $0.0935

The annual cost, which is 365 days, we have

Annual cost = $0.0935 × 365 = $34.123

(b) For the energy efficient 25-watt bulb, we have

25/1000 = 0.025kW

Power cost per annum =

0.025kW×$0.17 per kW·h×5.5×365 = $8.532

(c) Total cost of incandescent bulb = $0.89 total cost of using the incandescent bulb is $34.123 + $0.89 = $35.02

Total cost of using the energy efficient fluorescent bulb is about $3.49

Total cost of using the energy efficient bulb = $8.532 + $3.49 = $12.02

Total cost of incandescent bulb = $35.02 while total cost of energy efficient bulb is = $12.02

$12.02 <$35.02

Additional cost of fluorescent bulb is justified

8 0

4 years ago

At 20.°C, a 1.2-gram sample of Mg ribbon reacts rapidly with 10.0 milliliters of 1.0 M HCl(aq). Which change in conditions would

Pavlova-9 [17]

Answer: (2) decreasing the concentration of HCl(aq) to 0.1 M

Explanation: Rate of a reaction depends on following factors:

1. Size of the solute particles: If the reactant molecules are present in smaller size, surface of particles and decreasing the size increases the surface area of the solute particles. Hence, increasing the rate of a reaction.

2. Reactant concentration: The rate of the reaction is directly proportional to the concentration of reactants.

3. Temperature: Increasing the temperature increases the energy of the molecules and thus more molecules can react to give products and rate increases.

(1) Increasing the initial temperature to 25°C will increase the reaction rate.

(2) Decreasing the concentration of HCl(aq) to 0.1 M will decrease the reaction rate due to lesser concentration.

(3) Using 1.2 g of powdered Mg will increase the reaction rate due to large surface area.

(4) Using 2.4 g of Mg ribbon will increase the reaction rate due to high concentration of reactants.

7 0

3 years ago

Read 2 more answers

Predict what the population of the United States will be in the year 2010

s344n2d4d5 [400]

Answer:

308.7 million

Explanation:

is my prediction

5 0

3 years ago

According to Hund's rule of maximum spin multiplicity, how many singly-occupied orbitals are there in the valence shells of the

leva [86]

Answer:

A) carbon - 2

B) cobalt - 3

C) sulfur - 2

D) fluorine - 1

E) titanium - 2

F) germanium - 2

Explanation:

Hund's rule of maximum multiplicity:-

Firstly, every orbital which is present in the sublevel is singly occupied and then the orbital is doubly occupied.

(A) Carbon.