All categories

3 years ago

Help me please I don’t understand

Chemistry

2 answers:

Delvig [45]3 years ago

6 0

Natural selection and competition :)))))))

Anton [14]3 years ago

4 0

Answer:

1:Natural selection

2: competition

Natural selection; the process by which organisms with variations most suited to their local environment survive and leave more offspring.

Competition: The struggle between organisms to survive in a habitat with limited resources (food, water, shelter)

You might be interested in

__PbSO4 → __ PbSO3 +__O2<br><br> Balance the equation and indicate the type of reaction

shutvik [7]

<h2>Answer :2PbSO4 → 2PbSO3 + O2 </h2>

5 0

3 years ago

You leave for school late when you are pulled over by a police officer for speeding. He clocks you at 52 mi/hr . What is your sp

yawa3891 [41]

Answer:

Explanation:

The maximum speed limit in Prince Edward Island

unless otherwise posted is 80 kilometres per hour

(km/h). The basic speed limits are:

• 40 km/h (25 mph) in most municipalities

(municipalities may establish the maximum

speed limit within their boundaries);

• 50 km/h (30 mph) in urban areas;

• 60 km/h (40 mph) in school zones designated as

such by the erection of signs at the entrance and

the exit, between 8 a.m. and 5 p.m. when

children are present on or near the highway on

school days;

• 80 km/h (50 mph) on most provincial highways;

and

• 90 km/h (55 mph) on the TransCanada and

other designated highways.

Posted speed limits indicate the maximum safe

speed under favourable driving conditions.

3 0

4 years ago

In which orbital does an electron in a nitrogen atom experience the greatest shielding? In which orbital does an electron in a n

Charra [1.4K]

Explanation: Electron shielding could be defined as the reduction or mitigation in the effective cloud due to the differences in the attractive force of the nucleus on the electrons of an atom. Electron shielding explains the protection from attractive forces afforded to the outer electrons by their inner compatriot.

In Nitrogen, there are 3 2p electrons in the 2p sub-level which are shielded by 4 inner electrons; 2 in the 1s level and 2 in the 2s level. Therefore, the electrons in the 2p sub-level enjoy the greatest shielding from the attractive force of the nucleus due to the shield afforded to the valence electrons by the 4 inner electrons .

8 0

4 years ago

Calculate your experimentally determined percent mass of water in Manganese(II) sulfate monohydrate. Report your result to 2 or

antoniya [11.8K]

Answer:

10.6%

Explanation:

The determined percent mass of water can be calculated from the formula of the hydrate by

dividing the mass of water in one mole of the hydrate by the molar mass of the hydrate and

multiplying this fraction by 100.

Manganese(ii) sulphate monohydrate is MnSO4 . H2O

1. Calculate the formula mass. When determining the formula mass for a hydrate, the waters of

hydration must be included.

1 Manganes 52.94 g = 63.55 g

1 Sulphur 32.07 g =

32.07 g 2 Hydrogen is = 2.02 g

4 Oygen =

64.00 g 1 Oxygen 16.00 = 16.00 g

151.01 g/mol 18.02 g/mol

Formula Mass = 151.01 + (18.02) = 169.03 g/mol

2. Divide the mass of water in one mole of the hydrate by the molar mass of the hydrate and

multiply this fraction by 100.

Percent hydration = (18.02 g /169.03 g) x (100) = 10.6%

The final result is 10.6% after the two steps calculations

4 0

3 years ago

What is the oxidation number for Al in Al₂O₃?

sesenic [268]

Oxygen in oxides has oxidation number -2.

<span>Al⁺³₂O⁻²₃

+3*2 -2*3=0</span>

4 0

4 years ago