Answer:
Animal cell lacks chloroplasts and a cell wall
Explanation:
Unlike animal cells, plant cells have chloroplasts and a cell wall. In a plant cell, the chloroplasts work to use photosynthesis in order to turn light into energy for the plant cell. Animal cells do not utilize light energy, and therefore do not carry out photosynthesis and do not have chloroplasts.
Additionally, the plant cell has a protective cell wall and a cell membrane, while animal cells only have a cell membrane. This is because the plant cells' cell wall provides additional strength and protection against outside factors, such as osmosis.
Answer:
HfCl3
Explanation:
Step 1
Divide the percent by mass of each element by its relative atomic mass
Hf- 62.2/178.5, Cl-37.4/35.5
0.348, 1.054
Step2
Divide through by the lowest ratio
0.348/0.348, 1.054/0.348
1, 3
Therefore the empirical formula is HfCl3
Answer:
Elements in the same period have same number of electronic shell and electron is increased by one in every coming element with in same electronic shell.
Explanation:
Consider the second period of periodic table. This period consist of eight elements lithium, beryllium, boron, carbon, nitrogen, oxygen, fluorine and neon.
Electronic configuration of lithium:
Li₃ = [He] 2s¹
Electronic configuration of beryllium:
Be₄ = [He] 2s²
Electronic configuration of boron:
B₅ = [He] 2s² 2p¹
Electronic configuration of carbon:
C₆ = [He] 2s² 2p²
Electronic configuration of nitrogen:
N₇ = [He] 2s² 2p³
Electronic configuration of oxygen:
O₈ = [He] 2s² 2p⁴
Electronic configuration of fluorine:
F₉ = [He] 2s² 2p⁵
Electronic configuration of neon:
Ne₁₀ = [He] 2s² 2p⁶
All these elements present in same period having same electronic shell and number of electron increased by 1.
Answer:
3.91 moles of Neon
Explanation:
According to Avogadro's Law, same volume of any gas at standard temperature (273.15 K or O °C) and pressure (1 atm) will occupy same volume. And one mole of any Ideal gas occupies 22.4 dm³ (1 dm³ = 1 L).
Data Given:
n = moles = <u>???</u>
V = Volume = 87.6 L
Solution:
As 22.4 L volume is occupied by one mole of gas then the 16.8 L of this gas will contain....
= ( 1 mole × 87.6 L) ÷ 22.4 L
= 3.91 moles
<h3>2nd Method:</h3>
Assuming that the gas is acting ideally, hence, applying ideal gas equation.
P V = n R T ∴ R = 0.08205 L⋅atm⋅K⁻¹⋅mol⁻¹
Solving for n,
n = P V / R T
Putting values,
n = (1 atm × 87.6 L)/(0.08205 L⋅atm⋅K⁻¹⋅mol⁻¹ × 273.15K)
n = 3.91 moles
Result:
87.6 L of Neon gas will contain 3.91 moles at standard temperature and pressure.
The correct option is D.
The hydrogen atoms that are attached to the nitrogen atom in the ammonia molecule are capable of forming hydrogen bond. The hydrogen bond that exist in the ammonia molecule is the reason why it shows higher boiling point compare to the other hydrides. Hydrogen bond occur in ammonia because ammonia is one of the most electronegative elements.
