Answer:
Explanation:
The formula for molality is:
There are 0.210 moles of KBr and 0.075 kilograms of pure water.
Substitute the values into the formula.
Divide.
The molality is <u>2.8 moles per kilogram</u>
Answer:
30 hot dogs
Explanation:
It is given that :
There are 4 packets of eight wieners, i.e. 4 x 8 = 32 wieners
There are 3 bags of ten buns, i.e. 3 x 10 = 30 buns
One hot dogs need 1 bun and 1 wiener to make a hot dog.
There are 30 buns, so 30 hot dogs can be made out by using all the 30 buns and the 30 wieners out of the 32 wieners.
Therefore, 30 hot dogs.
And the number of extra wieners left = 32 - 30 = 2 wieners.
Answer : The incorrect option is, The most of the mass of the atom comes from the electron cloud.
Explanation :
There are three basic particles of an atom which are neutrons, protons and electrons.
The nucleus which is present in the center of an atom that contains the neutrons and the protons. The protons are positively charged and neutrons has no charge.
The outer region of an atom contains the electrons and the electrons are negatively charged.
As per given options, the statement which is the most of the mass of the atom comes from the electron cloud is incorrect statement because the most of the mass comes from the nucleus in which protons and neutrons are present.
Answer:
B.0.2 J/g°C
Explanation:
From the attached picture;
- Heat attained in the solid phase is 200 Joules
- Change in temperature is 50°C ( from 0°C to 50°C)
- Mass of the solid is 20 g
We are required to determine the specific heat capacity of the substance;
- We need to know that Quantity of heat is given by the product of mass,specific heat capacity and change in temperature.
- That is; Q = mcΔT
Rearranging the formula;
c = Q ÷ mΔT
Therefore;
Specific heat = 200 J ÷ (20 g × 50°c)
= 0.2 J/g°C
Thus, the specific heat of the solid is 0.2 J/g°C
