If you mean the number of Significant Figures/Digits in 23.45, it would be 4. This is because every single non-zero digit is counted as a significant figure
The answer would be A. Genotype
Answer:
a) alkali metals
Explanation:
The element described above definitely belonged to the alkali metals, the first group on the periodic table. They show the properties indicated in the text.
- They are metals because only metals are lustrous and malleable. This eliminates the possibility of them being halogens and noble gases.
- Only group 1 metals reacts vigorously with water to form alkali.
- Alkali are aqueous solutions that are basic in nature.
- The reactivity of group 1 metals is due to their one extra electrons in the outer most shell.
- These electrons are easily and readily lost in order for such atoms to gain stability and replicate the nearest noble gases.
- The most reactive metal belongs to this group elements.
- This is why it is nearly impossible to find them occurring alone in free state.
- Some of the elements in this group are Li, Na, K, Rb, Cs and Fr.
- Transition metals have variable oxidation states and some can be found alone in nature.
The nucleus of an atom of the element is positively charged and atom has a hollow space inside it.
Explanation:
This experiment was conducted by Rutherford in this experiment. He placed a gold foil and surround it with a screen.
And He exposed gold foil in alpha particles rays in which he noticed that most rays passed through atom which conclude that atom has a large space, some rays get deflected and some reverse their path this show that the positive charge of nucleus of an atom.
Answer:
Few important points related to 
reaction:
1. is a one-step reaction that follows second order kinetics.
2. In reaction, a transition state is formed in situ.
3. Strong nucleophiles like 
are used in case of bi-molecular nucleophilic substitution reaction.
Ethyl acetate can be prepared by a second-order nucleophilic substitution reaction between acetic acid and ethyl bromide.
The reaction between acetic acid and ethyl bromide is drawn below:
