Answer: 1160 m
Explanation:
Speed = distance / time. Plug in 40 m/s for speed and 29 s for time in order to get the distance, 1160 m.
If the atom is neutral, it has the same number of protons as electrons. If there are 5 electrons, there are also 5 protons.
Answer: 0.72 grams
Explanation: Mass can be extracted from the formula of density. D=M/V where D is density and V is volume. Therefore:
18 g/cm^3 = M(25 cm^3) --> Divide by 18g/cm^3 by 25 cm^3 to isolate mass. --> <u>0.72 =M </u> --> Now, to find out which unit you need to use for mass, just look at the density. You can see it is in g/cm^3, and cm^3 was already used for the volume. Thus, gram units are left, so that will be the unit needed, making the final answer 0.72 grams. Hope this helps :)
See from periodic table the proton or atomic number of elements u want to know about then as u know first electron shell can hold 2 electrons 2nd can hold eight as well as all others........protons are equal to electrons so divide proton number into shells but remember to use amounts which it can hold
CHEERS !!