Answer:
=1.068 ×10⁻¹³N
Explanation:
Force of gravity =Gm₁m₁/d² where G is the universal gravitation constant =G = 6.673 x 10-11 N m²/kg², m₁ and m₂ is the mass of object 1 and 2 respectively and d is the distance between them. First we change the distance into SI units i.e meters 25 km= 25000 m
F= (6.673 x 10⁻¹¹ N m²/kg²×1000 kg×1000 kg)/ (25000 m)²
=1.068 ×10⁻¹³N
Gas. Molecules in gas are able to move and vibrate around each other more freely than the molecules in liquids and/or solids due to the great amount of space in between them. Hope this helps! :)
Answer:
Amylase.
Explanation:
The process of digestion begin to start in mouth when food mix with saliva. An enzyme is released which is called Amylase help in digestion of carbohydrates.
Answer:
4.48 grams is the mass of potassium hydroxide that the chemist must weigh out in the second step.
Explanation:
The pH of the solution = 13.00
pH + pOH = 14
pOH = 14 - pH = 14 - 13.00 = 1.00
![pOH=-\log[OH^-]](https://tex.z-dn.net/?f=pOH%3D-%5Clog%5BOH%5E-%5D)
![1.00=-\log[OH^-]](https://tex.z-dn.net/?f=1.00%3D-%5Clog%5BOH%5E-%5D)
![[OH^-]=10^{-1.00} M=0.100 M](https://tex.z-dn.net/?f=%5BOH%5E-%5D%3D10%5E%7B-1.00%7D%20M%3D0.100%20M)

![[KOH]=[OH^-]=[K^+]=0.100 M](https://tex.z-dn.net/?f=%5BKOH%5D%3D%5BOH%5E-%5D%3D%5BK%5E%2B%5D%3D0.100%20M)
Molariy of the KOH = 0.100 M
Volume of the KOH solution = 800 mL= 0.800 L
1 mL = 0.001 L
Moles of KOH = n


n = 0.0800 mol
Mass of 0.0800 moles of KOH :
0.0800 mol × 56 g/mol = 4.48 g
4.48 grams is the mass of potassium hydroxide that the chemist must weigh out in the second step.
The effective nuclear charge is an innate property of a specific element. It is the pull of force that an electron feels from the nucleus. It is related to the valence electron by the equation: Z* = Z-S, where Z* is the effective nuclear charge, Z is the atomic number and S is the shielding constant.
For the following elements in the choices, these are their values of Z*:
Aluminum - +12.591
Beryllium - +1.912
Hydrogen - +1
Carbon - +4
The effective nuclear charge of Boron is +3. Thus, the answers are Aluminum and Carbon.