First off chlorine is not a metal so you can ignore that one.
Sodium and Rubidium are in group 1 of the periodic table and Magnesium is in group 2.
Group one metals are more reactive than group two because it is harder for the group two metals to lose their 2 valence (outer most) electrons.
As you go down group 1 there is an increase in the reactivity this is because as you go down there is an increase in the atomic radius which leads to more shielding. This weakens the electrostatic forces of attraction making it easier to lose the outermost electrons, therefore they are more reactive.
A2+. Group 2 elements form cations with 2+ charge.
Answer:
±0.005 g
Explanation:
The uncertainty depends on whether the measurement was obtained manually or digitally.
1. Manual
The minimum uncertainty is ±0.01 g.
It may be greater, depending on random or personal errors
2. Digital
Most measurements of mass are now made on digital scales.
A digital device must always round off the measurement it displays.
For example, if the display reads 20.00, the measurement must be between 20.005 and 19.995 (±0.005).
If the measured value were 20.006, the display would round up to 20.01.
If the measured value were 19.994, the display would round down to 19.99.
The uncertainty is ±0.005 g.
The scale shown below would display a mass of 20.00 g
Hey there!:
Molar mass NaCl = 58.44 g/mol
Number of moles:
n = mass of solute / molar mass
n = 15.6 / 58.44
n = <span>0.2669 moles of NaCl
hope this helps!</span>
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<u><em>Answer:</em></u>The compound ammonia given by fish is alkaline
<u><em>Explanation:</em></u><u>We can classify elements/compounds based on their pH values into three types:</u>
<u>acids:</u> these are compounds having pH value lower than 7
<u>neutral:</u> these are compounds having pH value equal to 7
<u>alkalies:</u> these are compounds having pH values higher than 7
This is shown in the attached image
We are given that the pH of the compound ammonia generated by the fish is
above 7.
According to the above explanation, compound ammonia would be an alkaline compound.
Hope this helps :)</span>