<h2><em>1. A</em></h2><h2><em>3. B</em></h2><h2><em>4. C</em></h2><h2><em>7. E</em></h2><h2><em>5. F</em></h2>
Unbalanced it should be 2Zn+2Hcl=2ZnCl2+H2
Answer:
equal to M
Explanation:
The mass of the fully melted mass and the initial solid will be the same. So, the mass of the melt is equal to M.
Mass is the amount of matter contained within a substance. Since only the phase changed and the amount of matter is still the same, the mass of the molten phase and the solid phase will remain the same.
We are correct to say that in the heating process no mass was destroyed or added in melting the solid.
A simple phase change that preserved the mass only occurred.
Answer:
1.7x10^8 Hz
Explanation:
Frequency could be explained as the number of occurrences of a repeating event at a time
Given:
wavelength = 1.8 meters
The frequency f of the waves can be calculated using f = c / λ
Where c (m/s) is the speed of the wave
λ (m) is the wavelength
Speed c= 3*10^8 m/s
Frequency f= 3*10^8 /1.8
Frequency= 1.7x10^8 Hz
Therefore,the frequency of waves from a radar detector is 1.7x10^8 Hz
Answer:
62.5 moles of O₂.
Explanation:
We'll begin by writing the balanced equation for the reaction. This is illustrated below:
2C₈H₁₈ + 25O₂ —> 16CO₂ + 18H₂O
From the balanced equation above,
2 moles of C₈H₁₈ reacted with 25 moles of O₂.
Finally, we shall determine the number of mole of O₂ needed to react with 5 moles of C₈H₁₈. This can be obtained as shown below:
From the balanced equation above,
2 moles of C₈H₁₈ reacted with 25 moles of O₂.
Therefore, 5 moles of C₈H₁₈ will react with = (5 × 25) / 2 = 62.5 moles of O₂.
Thus, 62.5 moles of O₂ is needed for the reaction.
